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Engine Room Motor Plants I

 

C Lube oil pumps taking suction from the sump of most small marine engines are usually __________. diaphragm type centrifugal type positive displacement type eductor type Auxiliary Engines
B Auxiliary diesel engines can be automatically shut down as a result of __________. low lube oil temperature low lube oil pressure high exhaust temperature high cooling water pressure Auxiliary Engines
C When a generator diesel engine is operated at partial load, as compared to full load, a decrease will occur in the average __________. piston speed fuel injection pressure combustion pressure on the power stroke compression pressure on the compression stroke Auxiliary Engines
A An auxiliary diesel generator continues to run after you try to shut down. Your next course of action should be to __________. block the flow of air supply to the engine engage the jacking gear secure the lube oil pump decrease control air pressure Auxiliary Engines
D What is the best way of stopping an over speeding diesel engine? Disconnect the battery cables from the starting motor. Drain the hydraulic fluid from the governor sump. Block the flow of cooling air to the radiator. Secure the fuel supply and block the air intake Auxiliary Engines
C Which of the listed conditions will result in the failure of an auxiliary diesel engine to shut down? Supplying high temperature inlet air. Maintaining a high exhaust back pressure. Lube oil entering in the air intake manifold. Carbon buildup on the over speed pawl. Auxiliary Engines
A In the auxiliary diesel engine, shown in the illustration, the __________. Illustration MO-0006 governor is linked to the fuel injection pump by vertical linkage explosion relief doors are clearly visible on both sides of the crankcase camshaft rotates at the same speed as the crankshaft engine oil filter is outboard of the electric starter Auxiliary Engines
B Which of the following test indicators should be considered the most significant factor in determining as to whether or not a diesel generator's lube oil should be drained and renewed? The oil appears black in color. An extremely high neutralization number. An extremely low precipitation number. An increase in flash point. Auxiliary Engines
B The valve cam slope angle determines the __________. engine torque characteristics acceleration rate of valve opening and closing engine fuel efficiency diameter of intake and exhaust valves Auxiliary Engines
D When two cams of the same diameter, one with tangential flanks and the other with convex flanks are compared, the cam with tangential flanks will cause___________. less valve seat wear greater valve lift more abrupt valve action less valve gear wear Auxiliary Engines
C The part labeled "G", as shown in the illustration, is a __________. Illustration MO-0040 connecting rod cap bearing shell connecting rod bushing piston bushing Auxiliary Engines
C In diesel engines, hydraulic valve lifters are used to __________. obtain greater valve lift create longer valve duration reduce valve gear pounding increase valve operating lash Auxiliary Engines
D The intake and exhaust valves used in a diesel engine are returned to their seats by __________. combustion pressure push rod pressure exhaust pressure spring force Auxiliary Engines
A Before any auxiliary diesel engine hydraulic starting system is opened for servicing or repair, you must __________. bleed off all hydraulic pressure from the system place all control levers in the 'HOLD' position block all hydraulic hoses using high pressure covers ensure that the hydraulic fluid reservoir is full Auxiliary Engines
A The service life of a worn aluminum piston for an auxiliary diesel, for which no spares are readily available, can be extended by __________. knurling the piston skirt surface increasing the dimensions of the ring land grooves building up the piston skirt with a liquid epoxy material and then remachining turning down the piston skirt to concentric values Auxiliary Engines
A In an auxiliary diesel engine, one reason for knurling the piston skirt is to __________. improve skirt lubrication transmit forces evenly allow for heat expansion improve the piston seal Auxiliary Engines
A A four-stroke cycle auxiliary diesel engine fuel cam has shifted from its original position
during maintenance. To ensure correct timing of the fuel pump, the intake and exhaust valves should be in what position when approaching top dead center for injection?
Intake and exhaust valves closed Exhaust valve open, intake valve closed Intake and exhaust valves open Intake valve open, exhaust closed Auxiliary Engines
A If an auxiliary diesel engine equipped with an electric starting system cranks very slowly after repeated attempts to start, the cause could be a/an __________. overheated motor windings ring gear with broken teeth low lube oil viscosity low compression pressure Auxiliary Engines
B In a four-stroke/cycle diesel engine, badly worn intake valve guides can cause excessive __________. cooling water temperatures lube oil consumption exhaust pressure exhaust temperatures Auxiliary Engines
D On small diesel engines, a noticeable decrease in the time interval between the replacement of the lube filter cartridge indicates __________. excessive oil temperature excessive oil pressure dirty air filter piston ring blow-by Auxiliary Engines
A A diesel engine may fail to start when being cranked, due to __________. insufficient compression high cetane number low lube oil viscosity high lube oil pressure Auxiliary Engines
C High exhaust temperature and black smoke exhausting from an auxiliary diesel engine can be caused by __________. plugged fuel nozzle holes excessive compression pressure engine overload low combustion temperature Auxiliary Engines
A One remedy for a high firing pressure, in addition to a high exhaust temperature in one cylinder of a diesel engine, is to __________. adjust the fuel rack retard fuel injector timing reduce fuel booster pump pressure increase scavenge air pressure Auxiliary Engines
D Starting aids such as glow plugs, are installed on __________. large, direct drive diesel engines diesel engines designed to burn residual fuels medium-speed, four-stroke/cycle diesel engines small diesel engines utilizing electric starting equipment Fuel
D Precombustion chambers, and energy cells in high-speed, small bore diesel engines all serve to increase __________. firing pressure ignition quality of fuel fuel/air ratio during compression turbulence Fuel
A Which of the combustion chambers shown in the illustration is referred to as an "energy cell" used in some small diesel engines? Illustration MO-0068 A B C D Fuel
B The purpose of the energy cell, or air cell, is to __________. cause auto ignition in the cell rather than in the main combustion chamber create a high turbulence within the main combustion chamber allow the spray to hit the piston rim rather than the cooler cylinder wall make a blast in the main chamber prior to the piston expansion stroke Fuel
B A diesel engine with a combustion chamber located between the crowns of two pistons is known as a/an __________. double-acting engine opposed piston engine single-acting engine horizontal acting engine Fuel
A A multi-orifice fuel injection nozzle is usually used with which of the listed types of combustion chamber? Open combustion chamber Precombustion chamber Turbulence chamber Energy cell Fuel
D Open combustion chambers are designed to __________. eliminate carbon buildup improve piston cooling prevent air charge turbulence provide proper fuel/air mixing Fuel
B What type of marine engine has a fuel nozzle and combustion chamber located between two pistons in a common cylinder liner? Horizontal reciprocating Vertical opposed piston Single acting in-line cylinder Double acting in-line cylinder Fuel
D Pre-combustion chambers differ from turbulence chambers in that pre-combustion chambers __________. allow fuel injection directly into the space above the piston do not contain the fuel injector nozzle tip contain the major portion of the total clearance volume contain a smaller portion of the total clearance volume Fuel
D Starting aids, such as glow plugs, are usually installed on __________. large, direct drive diesel engines diesel engines designed to burn residual fuels medium-speed, four-stroke/cycle diesel engines small diesel engines with electric motor starters Fuel
C The combustion of fuel for the illustrated engine is initiated by __________. Illustration MO-0020 fuel injection provided by a unit injector individual Bosch fuel pumps a spray of fuel into a turbulence combustion chamber fuel sprayed into an energy cell Fuel
A Which of the listed types of pre-combustion chambers is used in the diesel engine shown in the illustration? Illustration MO-0007 Turbulence chamber Energy cell Common rail Open type Fuel
D The desirable properties of a marine fuel oil should include __________. low heating value and high sulphur content low flash point and high viscosity high flash point and high viscosity high heating value and low sulphur content Fuel
A With respect to diesel fuel, the ease with which a cold engine will start is dependent upon the __________. ignition quality of the fuel high heating value of the fuel amount of carbon residue after combustion internal flow resistance in the injectors Fuel
D The ignition quality of diesel fuel becomes LESS critical as __________. lube oil additives are increased designed piston speeds are increased designed injection pressures are decreased designed engine speeds are decreased Fuel
B The cetane number rates fuels for diesel engines according to its __________. antiknock characteristics ignition qualities rates of vaporization viscosity Fuel
C Which of the following statements is true concerning the cetane number of diesel fuel? The cetane number affects the amount of injection lag. The cetane number is an indication of the fuel's viscosity. Ignition lag is reduced with fuels having a high cetane number. The cetane number is of little significance in the combustion process. Fuel
B A mixture of 45% cetane and 55% alpha-methyl-naphthalene is found to have the same ignition delay as a sample of diesel oil. The sample can be described as having a/an __________. cetane number of 55 cetane number of 45 octane number of 55 octane number of 45 Fuel
C If a particular liquid has a specific gravity of .96kg/dm3 at 77F, what will be the specific gravity of the liquid, as determined from the graph shown in the illustration, if the temperature is increased to 167F? Illustration MO-0113 .920 kg/dm3 .915 kg/dm3 .925 kg/dm3 .910 kg/dm3 Fuel
B The minimum fuel oil delivery pressure required for efficient injection depends primarily on the __________. degree of cylinder air turbulence maximum pressure in the engine cylinders during injection quantity of the fuel to be injected duration of the injection delay period Fuel Injection Systems
C Fuel injection systems are designed to primarily meter fuel, atomize fuel, and __________. create turbulence in the combustion chamber aid in completing cylinder scavenging inject fuel at the proper time minimize fuel penetration into the cylinder Fuel Injection Systems
A The degree of fuel atomization in a diesel engine cylinder depends primarily on __________. the size of the holes in the fuel nozzle timing of the pump supply pressure to the pump shape of the combustion chamber Fuel Injection Systems
A The purpose of the delivery check valve used in a diesel fuel injection jerk pump is to __________. assist in a quick cutoff of fuel injection allow oil backflow from the injector to the helix reduce fuel oil pressure between injection strokes meter the quantity of fuel delivered Fuel Injection Systems
B Regarding the fuel injector shown in the illustration, the purpose of piece #38 is to __________. Illustration MO-0059 adjust the fuel rack spring tension filter the fuel maintain fuel pressure at a preset level relieve excess fuel pressure to the suction side of the pump Fuel Injection Systems
C The amount of fuel delivered by a unit injector is controlled by the __________. camshaft main spring rack position engine speed Fuel Injection Systems
C In a unit injector, an upper helix and lower helix are machined in the lower part of the plunger for __________. facilitating plunger rotation positioning the control sleeve accurate metering of the fuel oil eliminating injection lag Fuel Injection Systems
B The control rack to a unit injector regulates fuel delivery by __________. altering spring tension on the plunger rotating the plunger and position of the helix regulating the lift of the check valve altering the actual length of the plunger stroke Fuel Injection Systems
A Which type of diesel engine fuel nozzle is shown in the illustration? Illustration MO-0059 Multi-hole Open Self-cleaning Pintle  Fuel Injection Systems
B The component shown in the illustration would be identified as a __________. Illustration MO-0097 slow speed engine cylinder liner lubricator slow speed engine fuel pump centrifugal flyweight governor injector cooling system pump Fuel Injection Systems
B The component identified as item #15 is used to __________. Illustration MO-0016 test injector popping pressure stop fuel delivery to the injector advance fuel pump timing increase the fuel pump delivery pressure Fuel Injection Systems
A In the large slow-speed main propulsion diesel engine shown in the illustration, the part labeled "G" is the __________. Illustration MO-0003 fuel oil pump jacket water pump crankcase exhaust fan lube oil pump Fuel Injection Systems
A According to the illustration, initial timing of fuel injection into the cylinder is controlled with the component that is identified as the letter __________. Illustration MO-0097 C H K I Fuel Injection Systems
A According to the illustration, fuel cutoff timing in the cylinder is controlled with the component that is identified as the letter __________. Illustration MO-0097 I H C K Fuel Injection Systems
D Injection pressure in a common rail fuel system is controlled by __________. engine speed varying the fuel pump piston stroke varying the injector needle valve clearance a bypass valve Fuel Injection Systems
A Diesel engine exhaust gas temperatures can be used to determine individual cylinder __________. performance horsepower output fuel consumption scavenge effect Fuel Injection Systems
D If sludge accumulates on the underside of a diesel engine piston, it will __________. cause blow-by chemically attack the piston skirt form an emulsion of lube oil and water raise the piston temperature Fuel Injection Systems
A The instrument shown in the illustration would be used on a diesel engine to __________. Illustration MO-0031 measure cylinder compression or firing pressures balance exhaust gas temperature readings measure exhaust gas pressure measure concentration of chromate in jacket water Fuel Injection Systems
D Before being shut down, a diesel engine should idle a few minutes in order to __________. prevent governor surging at shutdown make sure the fuel nozzles are flushed clean prevent pressure buildup in the fuel lines prevent damage from localized overheating Fuel Injection Systems
A If the relief valve on a diesel engine cylinder lifts, the cause could be due to __________. liquid in the cylinder low compression in the cylinder high exhaust temperature poor fuel penetration Fuel Injection Systems
A The diesel engine shown in the illustration can be fitted with a pyrometer at each exhaust elbow. If one of the cylinder pyrometers is reading significantly higher than the others, which of the following should be your FIRST action? Illustration MO-0005 Check the pump rack setting. Examine the water outlet header for evidence of blockage. Replace the fuel injector nozzle. Examine the exhaust valves for evidence of burning. Fuel Injection Systems
B White smoke issuing from the exhaust of an auxiliary diesel engine could mean __________. the engine is overloaded the engine is cold there is too much lube oil in the cylinders the turbocharger is fouled Fuel Injection Systems
A A diesel engine experiences a sudden loss in speed, accompanied by black exhaust smoke, with the fuel rack at maximum, and the speed remaining below normal. The probable cause is __________. engine overload leaky valves stuck or broken piston rings low air injection pressure Fuel Injection Systems
A Heavy fuel oils generally have an upper average ash content of 0.1% by weight. Which of the following conditions could be expected if the ash content increases above this amount? Increased exhaust valve wear Increased MEP Excessive bearing wear Glazing of the cylinder liners Fuel Injection Systems
B When running a large, dual fuel, main propulsion diesel engine on heavy fuel, which of the following precautions should be observed when switching from heavy fuel oil to diesel oil? The diesel oil must never be allowed to mix with the heavy fuel. The temperature of the fuel from the preheater should be gradually reduced after switching over the three-way valve. The heating steam to the preheater should be increased as soon as the diesel fuel passes through the three-way valve. The heating steam must be secured before the diesel oil passes through the three-way valve. Fuel Injection Systems
D When restarting a heavy fuel diesel engine that has been stopped for some time, the engineer should __________. increase the starting air pressure use a higher than normal cranking speed increase the fuel injection pressure use a fuel having a lower ignition temperature Fuel Injection Systems
D One cause of diesel engine fuel ignition delay is __________. mechanical flexibility in the pump mechanism low fuel booster pump pressure high fuel rack setting ignition quality of the fuel oil Fuel Injection Systems
A When a fuel injection nozzle overheats, which of the problems listed can be expected? The fuel metering will vary. The fuel will explode. The cylinder head will crack. The engine will stop. Fuel Injection Systems
D High cylinder firing pressure, accompanied by low exhaust temperature, can result from __________. improper fuel rack positioning lengthy exhaust valve duration extended operation at light load excessively early injection timing Fuel Injection Systems
A In the common rail system, excessive pressure in the header may be caused by __________. improper adjustment of the bypass valve a dribble in the fuel injection nozzle insufficient leak off through injection nozzle packing a malfunctioning injection nozzle Fuel Injection Systems
B Surface irregularities, such as erosion and pitting on injection pump plungers, will __________. increase ignition delay affect fuel oil metering affect engine performance at low speed only disappear due to fuel oil abrasion Fuel Injection Systems
A As shown in the illustration, which of the following conditions would be responsible for a "low pressure in oil outlet" alarm to be indicated? Illustration MO-0127 Throughput too low Separating temperature too low Controller set point changed Emergency stop button not reset Fuel Injection Systems
D While operating the fuel oil centrifuge shown in the illustration, the bowl fails to open for sludge ejection. The probable cause is that __________. Illustration MO-0012 one or more of the sludge ports is partially clogged the operating water pressure is too high the bowl disk set is clogged the seal ring on the operating slide is defective Fuel Injection Systems
A While operating the fuel oil centrifuge shown in the illustration, the fuel oil is being continuously ejected with the sludge and the seal water. The probable cause is the __________. Illustration MO-0012 gravity disk inside diameter is too large gravity disk inside diameter is too small back pressure is too low incorrect number of disks have been place in the disk stack Fuel Injection Systems
D Which of the following statements describes what will occur if the annular spaces, indicated by the letter "K" of the device shown in the illustration, became restricted? Illustration MO0112 The bowl will fail to close, but the unit will be capable of shooting while in operation. Operating water will be supplied through port "S". The unit will not start due to pressure/time delay relays. The bowl will fail to close when starting and the unit will not shoot when operating. Fuel Injection Systems
C For a diesel engine, approximately how long can an electric starter motor be operated continuously before damage may begin to occur due to overheating? Overheating the motor cannot occur. Not more than 90 seconds Not more than 30 seconds Not more than 60 seconds Fuel Injection Systems
A On a diesel engine with direct-cylinder admission air starting, a leaking air starting valve would be indicated by __________. an overheated starting air supply pipe excessive smoke from the engine exhaust carbon deposit on the exhaust valves early fuel ignition Fuel Injection Systems
B Which of the following conditions is most likely to occur if the electric starter motor pinion gear fails to disengage from the flywheel of a diesel engine after the engine has started? Engine will stop Starting motor will dangerously over speed Flywheel will be damaged Combustion gases will enter the air starting system Fuel Injection Systems
C When starting air is admitted, a diesel engine turns over very slowly without firing. The cause may be __________. an obstruction in an engine cylinder water accumulation in some engine cylinders low starting air pressure low scavenge air pressure Fuel Injection Systems
B When an additional load is applied to a diesel engine which is using an inadequately inflated air bladder clutch unit, you can expect __________. pneumatic seizure overheating because of slipping shoes chipped reduction gear teeth excessive wear on the thrust bearings Fuel Injection Systems
B Misalignment of the drive shaft and propeller shaft flanges can be detected by using a dial indicator or __________. inside micrometer feeler gage adjustable trammel sighting device Fuel Injection Systems
B The gear drive, shown in the illustration, can have the backlash determined best by using a __________. Illustration MO-0091 lead wire feeler gauge lash indicator red dye indicator Fuel Injection Systems
D The thrust bearing shown in the illustration has over eight years of ahead running time. Measurements show "i1" is 4 mm and "i2" is 1mm. Which of the following conditions is indicated and what steps should be taken, if any? Illustration MO-0121 A wear rate of 1.6 mm per year occurred. Although not excessive, this condition may require more frequent monitoring. The stops in which the thrust bearing block rides are worn, and it is necessary to return these to their original specifications. A wear rate of 1.6 mm per year is excessive and requires immediate assistance from the manufacturer's field support. No appreciable wear has occurred, and the proper maintenance procedures should continue to be followed. Fuel Injection Systems
A What could cause the bypass valve in a full-flow lubrication system to open? Clogged filter element Bypass valve setting is too high Check valve stuck open Fuel dilution of the lubricant Fuel Injection Systems
C Lube oil in the fresh water cooling system of a diesel engine may result from a __________. camshaft seizure lube oil pump failure lube oil cooler failure lube oil sump overflow Fuel Injection Systems
A Which of the following effects will excessively cold lube oil have on the operation of a diesel engine? The engine will crank slowly and may fail to start. The engine will over speed when started. The fuel oil supply will become diluted resulting in rough running. The cooling system will overheat causing the engine to stall. Fuel Injection Systems
D A four-stroke cycle main propulsion diesel engine fails to start at normal cranking speed with normal fuel pressure and ambient temperature. The reason for the failure could be __________. glazed liners or pistons high lube oil pressure excessive compression ratio excessive air leakage by rings and valves Fuel Injection Systems
D Clogged or partially obstructed exhaust ports on a diesel engine can cause __________. over speeding of the engine failure of the engine to shut down no effect of engine performance high exhaust temperatures Fuel Injection Systems
A A diesel engine may be hard to start if the __________. air intake is restricted engine is cranked too fast vibration dampener is faulty exhaust back pressure is low Fuel Injection Systems
B Combustion gas venting through the expansion tank can be caused by a __________. leaking oil cooler cracked cylinder head worn piston ring leaking exhaust valve Fuel Injection Systems
D Some diesel engines are fitted with a thermometer in the cooling water outlet from each cylinder. If the cooling water temperature from all cylinders begins to rise above normal, you should suspect __________. insufficient fuel delivery to all cylinders increased blow-by in all cylinders incomplete combustion in all cylinders overloading in all cylinders Fuel Injection Systems
D A diesel engine cylinder head can crack as a result of __________. a leaking oil control ring heat transfer from exhaust valves overheated intake valves restricted cooling passages Fuel Injection Systems
C Antifreeze solutions containing ethylene glycol should not be mixed with corrosion protection oils, as the resultant mixture __________. is dangerously flammable has a higher chloride content may cause frothing promotes scale buildup Fuel Injection Systems
B Oil accumulating in the exhaust piping or manifold of a diesel engine can be caused by __________. collapsed hydraulic valve lifters worn valve guides excessive crankcase vacuum excessive lube oil pressure Fuel Injection Systems
B If there is a 'clicking' sound in the valve compartment of a diesel engine, the cause may be __________. a worn wrist pin excessive valve lash worn connecting rod bearings All of the above. Fuel Injection Systems
B Excessive wear at part #11, as shown in the illustration, would result in __________. Illustration MO-0027 improper timing increased oil consumption lost compression low oil pressure Fuel Injection Systems
D If an auxiliary diesel engine equipped with an electric starting system cranks very slowly after repeated attempts to start, the cause could be a/an __________. low lube oil viscosity low compression pressure ring gear with broken teeth overheated motor windings Fuel Injection Systems
B A diesel engine may fail to start when being cranked, due to __________. high cetane number insufficient compression low lube oil viscosity high lube oil pressure Fuel Injection Systems
A High exhaust temperature and black smoke exhausting from an auxiliary diesel engine can be caused by __________. engine overload low combustion temperature plugged fuel nozzle holes excessive compression pressure Fuel Injection Systems
A Crank web deflection readings will give a positive indication of __________. worn main bearing journals crankpin misalignment slack thrust bearings bearing shells shim dimensions Fuel Injection Systems
B Prior to starting, the purpose of turning over a main propulsion diesel engine with the cylinder test cocks open, is to __________. test the starting system remove condensation and other liquids from the cylinders check the compression check for proper lube oil pressure Fuel Injection Systems
A The thrust bearing shown in the illustration has over eight years of ahead running time. Measurements show "i1" is 4 mm and "i2" is 1mm. Which of the following conditions is indicated and what steps should be taken, if any? Illustration MO-0121 No appreciable wear has occurred, and the proper maintenance procedures should continue to be followed. A wear rate of 1.6 mm per year occurred. Although not excessive, this condition may require more frequent monitoring. The stops in which the thrust bearing block rides are worn, and it is necessary to return these to their original specifications. A wear rate of 1.6 mm per year is excessive and requires immediate assistance from the manufacturer's field support. Fuel Injection Systems
B If a single cylinder relief valve on a main propulsion diesel engine begins to lift, but it is not possible to secure the engine, which of the following actions should be taken? Increase the cooling water flow to the engine. Secure or reduce fuel to that cylinder. Screw down on the pressure adjusting spring to decrease popping pressure. Readjust the injection timing. Fuel Injection Systems
D Excessive vibration from an auxiliary boiler could be caused by __________. combustion pulses insufficient air to the burner loose hold-down bolts All of the above. Fuel Injection Systems
C High stack temperature occurring in an auxiliary boiler could be a result of __________. insufficient air for combustion complete combustion in the furnace secondary combustion in the uptake high fuel oil temperature Fuel Injection Systems
D Which of the following conditions could cause the feed pump for an auxiliary boiler to lose suction? Increased suction head pressure Decreased feed water temperature Pump recirculating line being open too much Excessive feed water temperature Fuel Injection Systems
A If the wearing rings of device "7" shown in the illustration become worn, how will the evaporation rate in "23" be affected? Illustration MO-0111 The rate of evaporation will decrease. The rate of evaporation is dependent on the level of vacuum maintained within the unit, and not the flow of water to the unit. Device "7" does not use wearing rings, as these are normally positive displacement pumps. The rate of evaporation will not be affected as the standby pump, labeled "8" will be used instead. Fuel Injection Systems
D If valve "D" is opened during the normal operation of the distiller shown in the illustration, which of the events listed will occur? Illustration MO-0111 The amount of vapor formed in the evaporator will increase. The jacket water cooler will be overloaded, eventually causing a critical engine alarm. The output of pump "7" will increase with a corresponding increase in pressure. The amount of vapor being formed in the evaporator will decrease. Fuel Injection Systems
A What would be the first indication that a tube leak has occurred in area "23"? Illustration MO-0111 The level in area "1" would decrease. The level in area "1" would increase. The level in area "3" would increase. The level in area "3" would decrease. Fuel Injection Systems
D Which of the conditions listed would indicate a large condenser tube leak within the distiller shown in the illustration? Illustration MO-0111 A decrease in the level of the main engine expansion tank as indicated by a low level alarm. An increase in distiller output resulting from the combination of jacket water and the distillate produced. A slow continuous rise in the lube oil cooler outlet temperature indicated at device "4". The activation of the salinity monitoring equipment's annunciator circuit. Fuel Injection Systems
D If the operating speed of a diesel engine increases without an apparent change in the engine control settings, you may suspect a __________. clogged intake air intercooler control air leak leaking air starting valve malfunctioning governor Fuel Injection Systems
D Governor hunting is caused by __________. governor under-control excessive speed droop insufficient speed droop governor over-control Fuel Injection Systems
D The hunting of a diesel engine may be caused by __________. excessive speed droop insufficient speed droop excessive sensitivity low governor power Fuel Injection Systems
C If the speeder spring of a main propulsion diesel engine governor breaks while operating at full load, the engine RPM will __________. increase until the over speed trip actuated hunt until stabilized by the droop rod decrease to a slightly lower value remain the same until manually changed Fuel Injection Systems
C A diesel engine operates erratically, over speeds, and fails to restart when cranked at normal speed. Which of the following problems is the most likely cause for the engine failing to restart? Improper governor operation due to excess oil pressure Damage to the governor due to excessive speed Failure to reset the over speed trip Failure to reposition the fuel rack Fuel Injection Systems
A A propulsion engine, using the speed control circuit shown in the illustration, fails to function at speeds lower than the low end of the critical speed range. Which of the following statements describes what should be done to correct this malfunction? Illustration MO-0114 Device 17A needs to be replaced, repaired, or reset to the set point coinciding with the RPM value for the low end of the critical speed range. The critical speed range will be varied as the set points of 17A or 17B are reset, therefore, another segment of the speed control circuit must be repaired. To increase the critical speed range of the engine, reduce the set point of 17A and 17B respectively, to .80 bar and 1.0 bar. Both 17A and 17B need to be reset to decrease the critical speed range, although this procedure will increase the operating range of the engine. Fuel Injection Systems
C The governor utilized with the device shown in the illustration has become inoperative while the vessel is underway at sea. Which of the following statements describes what action should be taken? Illustration MO-0119 It is necessary to disconnect the shuttle valve from the throttle lever horizontal bar, in order to effectively jump out the pneumatic engine enable control circuit. The governor should be replaced with one that has been proven to be useful in isochronous applications. The engine speed can be controlled using the fuel control lever without changing the position of the maximum fuel stop. The linkage to the shut down servomotor and the governor output shaft must be disconnected in order to operate the engine via the fuel control lever. Fuel Injection Systems
C The power output of a turbo-charged diesel engine will drop if the cooling water flow through the after cooler is interrupted because the __________. turbocharger stalls exhaust pressure increases air charge density decreases scavenge effect increases Fuel Injection Systems
D Corrosion and grooving on the blading of an exhaust driven turbocharger is caused by certain components of residual fuel oils. These components are vanadium, sodium, and __________. copper carbon hydrogen sulfur Fuel Injection Systems
D Excessive mechanical and pulsating vibrations developed in a main propulsion diesel engine may be more likely to cause damage to an attached __________. scavenged air pump because it is designed for steady state operation rather than pulsating gas load reciprocating scavenge pump because of its direct linkage to the crankshaft centrifugal cooling water pump because of the close tolerances required between the impeller rim and the volute gas driven turbocharger because it has a wide speed range, high operating temperatures and close tolerances. Fuel Injection Systems
A Differential needle valves used in fuel injectors are directly closed by __________. spring force firing pressure cam action fuel oil pressure Fuel Injection Systems
B Carbon deposit build up on the injection nozzle orifice is least likely to occur when using which type of fuel injector nozzle? Hole Pintle Multi-pintle Multi-hole Fuel Injection Systems
B The item labeled #16 in the illustration is a stack of spring washers. Their function is to __________. Illustration MO-0062 permit accurate stretch gauge measurement of bolt elongation during installation maintain the same hold-down force on the injector regardless of varying engine operating temperatures prevent bolt failure by allowing limited movement of the injector when excessively high cylinder pressures are developed absorb the high pressure pulses developed during the fuel injection process Fuel Injection Systems
A Regarding the fuel injector shown in the illustration, the purpose of piece #38 is to __________. Illustration MO-0059 filter the fuel adjust the fuel rack spring tension maintain fuel pressure at a preset level relieve excess fuel pressure to the suction side of the pump Fuel Injection Systems
D Which type of diesel engine fuel nozzle is shown in the illustration? Illustration MO-0059 Open Pintle Self-cleaning Multi-hole Fuel Injection Systems
D The amount of fuel delivered by a unit injector is controlled by the __________. engine speed main spring camshaft rack position Fuel Injection Systems
B The indicated position of the fuel injection pump plunger as shown in the illustration will provide fuel delivery to the diesel engine in an amount approximately equal to __________. Illustration MO-0061 normal fuel flow maximum fuel flow zero fuel flow light fuel flow Fuel Injection Systems
D Which of the following statements represents the function of the plunger flange labeled "A" shown in the illustration? Illustration MO-0061 It prevents the plunger from rotating in the barrel. It limits the actual stroke of the plunger. It takes the plunger off stroke when injection is completed. It transmits the control rack setting to the plunger. Fuel Injection Systems
A As shown in the illustration of the fuel injection pump, the section designated as "M" is referred to as the __________. Illustration MO-0061 plunger helix plunger relief shoulder plunger control tab plunger sleeve Fuel Injection Systems
A As shown in the illustration of the fuel injection pump, the component labeled "N" would be identified as the __________. Illustration MO-0061 Barrel Sleeve Control Rack Plunger Fuel Injection Systems
C As shown in the illustration of the fuel injection pump, the function of the area designated as "L" is to __________. Illustration MO-0061 relieve excessive injector discharge pressure control the fuel injection rate allow excess fuel oil to return to the fuel oil system provide for plunger lubrication Fuel Injection Systems
A In the illustration shown, moving the component labeled "E", further to the left, will result in __________. Illustration MO-0061 a shorter fuel injection cycle a greater quantity of fuel injected an increase in the cylinder mean effective pressure an increase in fuel pump delivery pressure Fuel Injection Systems
D What is the purpose of the "window" installed in the housing of an individual jerk pump? To set up the fuel rack calibration in cubic millimeters. To check that fuel oil return passages are clear. To check for sludge on the pump barrel. To allow the pump to be timed to the engine. Fuel Injection Systems
A Injection pressure in a common rail fuel system is controlled by __________. a bypass valve varying the injector needle valve clearance engine speed varying the fuel pump piston stroke Fuel Injection Systems
C The component shown in the illustration would be identified as a __________. Illustration MO-0097 slow speed engine cylinder liner lubricator centrifugal flyweight governor slow speed engine fuel pump injector cooling system pump Fuel Injection Systems
C The component shown in the illustration would be identified as a __________. Illustration MO-0097 slow speed engine cylinder liner lubricator centrifugal flyweight governor slow speed engine fuel pump injector cooling system pump Fuel Injection Systems
C The component identified as item #15 is used to __________. Illustration MO-0016 test injector popping pressure advance fuel pump timing stop fuel delivery to the injector increase the fuel pump delivery pressure Fuel Injection Systems
A In the large slow-speed main propulsion diesel engine shown in the illustration, the part labeled "G" is the __________. Illustration MO-0003 fuel oil pump jacket water pump lube oil pump crankcase exhaust fan Fuel Injection Systems
A According to the illustration, initial timing of fuel injection into the cylinder is controlled with the component that is identified as the letter __________. Illustration MO-0097 C H I K Fuel Injection Systems
D According to the illustration, fuel cutoff timing in the cylinder is controlled with the component that is identified as the letter __________. Illustration MO-0097 H K C I Fuel Injection Systems
D When disassembling or assembling an injection pump plunger and barrel you should __________. work over a linoleum-type surface always keep the plunger and barrel as a matched set keep the parts immersed in diesel fuel All of the above. Fuel Injection Systems
A You are testing a closed fuel injection nozzle using a nozzle tester. A pressure slightly less than design valve opening pressure is applied. If no fuel appears at the spray tip, the __________. needle valve is operating properly nozzle orifices are too small needle valve spring is defective nozzle orifices are eroded Fuel Injection Systems
A Because of the close tolerances used in diesel engine fuel oil pumps, a worn plunger requires __________. replacing the plunger and the barrel highly polishing both the plunger and barrel grinding the spare plunger to the barrel replacing plunger only Fuel Injection Systems
C Uneven bolt tightening during the installation of a fuel injection pump can result in __________. high torsional shock to fuel lines ignition delay binding of pump moving parts improper pump-to-engine timing Fuel Injection Systems
C Which of the fuel nozzles listed requires the LEAST maintenance? Open Single hole Pintle Multi-hole Fuel Injection Systems
A Which of the following statements concerning the factors affecting ignition delay is correct? An increase in coolant temperature will decrease ignition delay. An increase in intake air temperature will increase ignition delay. An increase in compression ratio will increase ignition delay. An increase in combustion chamber turbulence will increase ignition delay. Fuel Injection Systems
B One cause of diesel engine surging can be a result of __________. low compression injection pump fuel rack binding or sticking solenoid stuck open fuel booster pump pressure too high Fuel Injection Systems
A Heat damage to fuel injection nozzles can be prevented by avoiding __________. long periods of engine overload metallic contact between nozzles and cylinder heads hard carbon deposit and varnish on the nozzles excessive fuel oil temperature Fuel Injection Systems
B One cause of diesel engine surging can be a result of __________. low compression injection pump fuel rack binding or sticking solenoid stuck open fuel booster pump pressure too high Fuel Injection Systems
C In the common rail system, excessive pressure in the header may be caused by __________. a malfunctioning injection nozzle insufficient leakoff through injection nozzle packing improper adjustment of the bypass valve a dribble in the fuel injection nozzle Fuel Injection Systems
B High firing pressures and a low exhaust temperature in a diesel engine may result from __________. increased exhaust system back pressure early fuel injection timing early exhaust valve opening low scavenge air temperature Fuel Injection Systems
A Surface irregularities, such as erosion and pitting on injection pump plungers, will __________. affect fuel oil metering affect engine performance at low-speed only disappear due to fuel oil abrasion increase ignition delay Fuel Injection Systems
C While examining a used fuel injection nozzle(s), one finds worn and enlarged orifices. What does this indicate about that cylinder's performance prior to nozzle replacement(s)? Volume of atomization is increased, penetration is reduced, vaporization is increased, efficiency is not effected. Volume of fuel injected is increased, reduced injection pressure, decreased ignition delay. Reduced combustion efficiency, increased ignition delay, reduced atomization, prolonged penetration. Penetration is increased, air/fuel mixture is increased, cylinder efficiency is not substantially effected. Fuel Injection Systems
A Injection lag in a diesel engine may be caused by __________. the flexibility of high-pressure fuel lines a decrease in the air temperature a decrease in compression pressure a change in the cetane number of the fuel Fuel Injection Systems
C Poor combustion in a diesel engine can be caused by __________. high scavenge air pressure low exhaust pressure low compression temperature high compression pressure Fuel Injection Systems
C Diesel fuel oil having a low cetane rating can result in __________. smoother engine operation reduce ignition lag combustion knock improved cold weather starting Fuel Injection Systems
B Faulty operation of diesel engine fuel injection nozzles can be a direct cause of __________. excessive fuel nozzle holder cooling sediment in the fuel supply improper atomization of the fuel distortion of the fuel spray pattern Fuel Injection Systems
C Which of the following problems is the main source of fuel pump and injection system malfunctions? Coated fuel lines Improper lubrication Air in the fuel system Excessive vibration Fuel Injection Systems
D High cylinder firing pressure, accompanied by low exhaust temperature, can result from __________. improper fuel rack positioning lengthy exhaust valve duration extended operation at light load excessively early injection timing Fuel Injection Systems
D Problems with the diesel engine fuel injection pump are usually caused by __________. kinked fuel lines excessive engine vibration improper adjustment contaminated fuel Fuel Injection Systems
C When is fuel injected into a cylinder of diesel engines? After combustion gases in the cylinder have expanded. As air is taken into the cylinder. After air in the cylinder is compressed. Before air in the cylinder is compressed. Fuel Oil and Combustion
A The time between injection and ignition of the fuel is known as __________. ignition delay after burning ratio injection lag turbulence lag Fuel Oil and Combustion
B For a given fuel, a change in the compression ratio will affect the ignition lag by which of the listed means? An increase in compression ratio will increase the ignition lag. An increase in compression ratio will decrease the ignition lag. A decrease in ignition lag will increase the compression ratio. A decrease in compression ratio will decrease the ignition lag. Fuel Oil and Combustion
B The rate of pressure rise during the period following fuel ignition in a diesel engine is influenced by the length of the ignition delay period and the __________. volumetric efficiency turbulence of the air charge fuel efficiency valve overlap Fuel Oil and Combustion
D The pressure in an operating diesel engine cylinder continues to rise for a short period after the piston passes top dead center as a result of the __________. fuel injection occurring at that point and combustion begins exhaust and intake valves just closing maximum compression pressure is just being attained expansion during the combustion process Fuel Oil and Combustion
D Fuel combustion in a diesel engine cylinder should begin just before the piston reaches top dead center and should __________. end when fuel injection has been completed be completed exactly at top dead center end at bottom dead center continue through the after-burning period Fuel Oil and Combustion
D Which statement about diesel engine combustion is true? Maximum combustion pressure is reached before TDC. Combustion does not begin until the piston starts down on the power stroke. Turbulence in the cylinder causes a delay in ignition. Maximum cylinder firing pressure is not developed until the piston passes TDC. Fuel Oil and Combustion
D Fuel combustion in a diesel engine cylinder should begin just before the piston reaches top dead center and should __________. end when fuel injection has been completed  be completed exactly at top dead center end at bottom dead center continue through the afterburning period Fuel Oil and Combustion
C Catalytic fines comprised of aluminum oxide and/or silicon dioxide are a common contaminant of residual fuels. Which diesel engine components would be most effected by catalytic fines in fuel? High pressure fuel pumps and cylinder liners. Fuel injectors and piston rings. High pressure fuel pumps and fuel injectors. Fuel injectors and turbocharger blading. Fuel Oil and Combustion
C Does sulfur content of heavy fuel oil effect the fuel rate of a diesel engine and why or why not? No, it only effects possible acid corrosion of engine components. Yes, it may increase wear of engine components and thus piston ring blow-by. Yes, high sulfur content decreases calorific value of fuel. No, it does not effect efficiency of combustion. Fuel Oil and Combustion
C As Chief Engineer of a slow speed diesel propelled vessel operating with constant slip, when considering the effect on the fuel consumption in barrels per mile of a planned increase in operating RPM you utilize which of the following? fuel consumption varies as the square of the shaft RPM fuel consumption varies directly proportional to the shaft RPM fuel consumption varies as the cube of the shaft RPM fuel consumption varies inversely with the shaft RPM Fuel Oil and Combustion
B You are on board a vessel with a slow speed crosshead type engine. The fuel just received has a significantly lower sulfur content then the previous bunkers. Which of the following would be a concern due to the reduced sulfur content? Fuel injection temperature Base number of the cylinder oil Fuel supply system pressure Purifier gravity disk size Fuel Oil and Combustion
A Heavy fuel oils generally have an upper average ash content of 0.1% by weight. Which of the following conditions could be expected if the ash content increases above this amount? Increased exhaust valve wear Increased MEP Excessive bearing wear Glazing of the cylinder liners Fuel Oil and Combustion
B While bunkering heavy fuel, what quick/easy test can one perform onboard to determine the compatibility of 'old' with 'new' fuel? Take equal samples of both fuels, elevate their temperature, mix them vigorously. If no frothing occurs, they are compatible. Use blotter paper with a single concentric drop of 'old' and 'new' fuel, if they do not form separate circles, the fuels may be deemed compatible. Mix two equal samples of the two fuels at elevated temperatures and determine if they become a homogeneous mixture. Perform a running viscosity test of both fuels, at the same temperature, if the viscosities are equal, they should be compatible. Fuel Oil and Combustion
D The purpose of the interlocked three-way valve shown in the illustration is to __________. Illustration MO-0058
recirculate fuel through the heater during warm-up control the rate of fuel oil flow to the engines act as an emergency fuel shut off, regardless of the fuel being used change fuel from heavy to light oil or vice-versa while insuring that oil is returned to the proper day tank Fuel Systems
A For optimum results, centrifugal purification of heavy fuel oil should be accomplished with the fuel at the lowest practicable __________. throughput additive percent cetane number TBN number Fuel Systems
A Which of the listed substances can be satisfactorily removed from diesel fuel by centrifuging? Sludge Gasoline Fuel oil Lube oil Fuel Systems
C Which factor determines the size of the ring dam for a fuel oil centrifugal purifier? The viscosity of the fuel. The quantity of water to be removed from the fuel. The specific gravity of the fuel. The quantity of dirt to be removed from the fuel. Fuel Systems
B Whether using a centrifuge or a simple filter, oil cleaning and filtration will be the most effective when the oil is at a __________. high temperature and a high viscosity high temperature and a low viscosity low temperature and a high viscosity low temperature and a low viscosity Fuel Systems
B The temperature of the contaminated fuel oil fed to the centrifuge shown in the illustration should be __________. Illustration MO-0012 greater than 212F 203F to less than 212F 160F to 180F selected according to the oil's viscosity index Fuel Systems
B All alarms occurring on the control unit of the device shown in the illustration will __________. Illustration MO-0127 not be indicated in numerical order shut off the oil feed to the separator
cause the separator to automatically enter the sludge discharge cycle
be initiated by the water transducer or vibration switch Fuel Systems
A How may water be removed from the bowl of the separator as shown in the illustration? Illustration MO-0127 The water may be removed through the water drain valve or through the sludge ports during the sludge discharge cycle.
The separator is used to remove solids from the processed liquid, therefore the accumulation of water does not present a problem.
When the unit is secured and the bowl stops rotating, the water is drained off the bottom of the bowl through orifice ports.
Water may only be removed from the bowl when the unit is secured and the bowl hood is removed. Fuel Systems
A Which of the following statements represents the working principle of the water transducer used with the separator shown in the illustration? Illustration MO-0127 The probe and sensor measure the dielectric constant through capacitive reactance of the process fluid.
As the water content in the oil decreases, the dielectric constant increases.
The capacitor completes part of the inductive circuit which monitors pressure changes.
All of the above. Fuel Systems
D The device shown in the illustration can be automatically or manually desludged. The closing sequence at the end of the desludging cycle is initiated by opening which of the labeled components listed below? Illustration MO-0012 R  P F Q Fuel Systems
A The greatest difference between the centrifuge bowl shown in the illustration and that of a tubular bowl, with straight, vertical, interior surfaces, is that the illustrated unit __________. Illustration MO-0012 is self desludging
rotates at 1000 rpm higher than the old tubular bowl type
rotates at 1000 rpm slower than the old tubular bowl type
does not require a discharge ring when operated as a separator Fuel Systems
A Which of the labeled figures illustrated, represents the correct alignment mark relationships of a properly reassembled centrifuge bowl? Illustration MO-0022 A B  C D Fuel Systems
D Which of the following precautions should be taken prior to starting the separator shown in the illustration? Illustration MO-0127
Make sure the separator is properly assembled.
Check for the correct oil level in the gear housing. Release the bowl brake and confirm proper valve line up. All of the above. Fuel Systems
C How is oil supplied to the device shown in the illustration? Illustration MO-0127 An attached positive displacement pump supplies oil to the separator. The oil inlet paring disc creates a low pressure in the suction piping. In this arrangement an independent pump is utilized.
This purifier as well as most others will be installed in the lower engine room to make use of gravitational forces. Fuel Systems
C Which of the following statements is accurate concerning the vibration sensing device used with the separator shown in the illustration? Illustration MO-0127 Vibration sensors are not used with centrifuges currently installed on diesel vessels due to excessive vibrations developed by the main propulsion units.
 o
The vibration switch is sensitive to vibration in a direction horizontal to its mounting base and is normally installed low on the separator where movement is magnified. The detector mechanism consists of an armature suspended on a flexure pivot and restrained from motion by a permanent magnet acting through a small air gap.
 o
The detector is so arranged to prevent abnormal harmonic frequencies from being developed while the separator is passing through its critical speed range. Fuel Systems
B The system shown in the illustration utilizes a water transducer which is __________. Illustration MO-0127 a mechanical/electrical device with a variable dc output located in the oil outlet piping
similar to those used in sonar systems
essential in monitoring the amount of water entering the separator Fuel Systems
D In the device shown in the illustration, the component lettered "A" is the __________. Illustration MO-0012 seal water input port
heavy phase discharge port light phase discharge port dirty oil input port Fuel Systems
C The device labeled "A", shown in the illustration, is known as the __________. Illustration MO-0112 centripetal pump cover bowl assembly hood regulating ring  kinetic converter Fuel Systems
B Which of the following statements describes "N" shown in the illustration? Illustration MO-0112 the included angle of oil flow the centrifuge disc stack the sole direction of heavy phase flow the relative size of the separation zone Fuel Systems
C Item "O" of the device shown in the illustration is the __________. Illustration MO0112 fair flow nut inlet directional guide spindle nut impeller locking device Fuel Systems
D The wear liner shown in the illustration is indicated by the letter __________. Illustration MO-0112 "G" "N" "P" "R" Fuel Systems
C The discharge nozzle shown in the illustration, is indicated by the letter __________. Illustration MO-0112 A K S X Fuel Systems
D The gasket "U" shown in the illustration, is used to seal the liquid space below the __________. Illustration MO-0112 ring dam inner bowl outer bowl sliding piston Fuel Systems
D The port "X" shown in the illustration allows water to enter the adjoining chamber. During what cycle of operation will this occur? Illustration MO-0112 Operating back flush cycle Bowl retention cycle Clarification cycle Sludge discharge cycle Fuel Systems
D The area indicated by the letter "W", shown in the illustration is correctly termed the __________. Illustration MO-0112 closing chamber parting chamber upper sliding piston chamber opening chamber Fuel Systems
D What is used as the primary operating medium during the sludge discharge cycle, shown in the illustration? Illustration MO-0112 Light phase liquid
 o
Heavy phase liquid Hydraulic fluid Water Fuel Systems
C Where does the shoot cycle operating liquid first come in contact with the rotating forces of the device shown in the illustration? Illustration MO-0112 While traveling under disc stack "N". At the inlet cone labeled "O". In the opening chamber labeled "L".
At the inlet orifice labeled "S". Fuel Systems
B The unit shown in the illustration is beginning the sludge discharge cycle. The operating liquid solenoid valve has been energized and space "J" is filling up. Which of the following actions should occur next? Illustration MO-0112 The liquid enters the opening space, controlled by the discharge port "S", thereby causing the sliding bowl bottom to move upwards. The liquid enters via port "X" into the opening space with the net resultant force causing the piston slide to move down. The liquid enters via port "X", travels through the closing chamber, and exits port "S", maintaining an upward force against the bowl bottom, The liquid remains trapped in space "J", developing an upward force to open the bowl. Fuel Systems
A The device labeled 'C' shown in the illustration is known as the __________. Illustration MO-0112 upper locking ring
lower paring device
upper paring gasket
pump lock Fuel Systems
C What terminates the sludge discharge cycle of the device shown in the illustration? Illustration MO-0112 The solenoid valve opens, directs high pressure fluid into the closing chamber, and results in an upward movement of the sliding piston. The solenoid valve closes, reduces the water pressure to the paring chamber, and allows the spring force to move the sliding piston upward. The solenoid valve closes, allows the water in the opening chamber to bleed off through "S", and the sliding piston moves upward due to the force developed in area "J". The solenoid valve closes, allows the weight of the sliding piston to oppose the low water pressure, and moves it along the axis of the spindle. Fuel Systems
B During the normal operation of the centrifuge shown in the illustration, the operating liquid solenoid and bypass valves for the cleaning cycle should be in which position? Illustration MO-0112 The solenoid valve is closed and the bypass valve is open. The solenoid valve is closed and the bypass valve is closed. The solenoid valve is open and the bypass valve is closed. The solenoid valve is open and the bypass valve is open. Fuel Systems
D The device labeled "B", shown in the illustration, is known as the __________. Illustration MO-0112 upper ring chamber set of regulating rings comminuting device centripetal pump chamber cover Fuel Systems
B The device labeled "D", as shown in the illustration, is the bowl __________. Illustration MO-0112 hood top cover hub Fuel Systems
D The item indicated by the letter "F" of the device shown in the illustration is the __________. Illustration MO-0112 guide band guide pin locating dowel pin upper bowl gasket Fuel Systems
B The device labeled "H", shown in the illustration is referred to as the __________. Illustration MO-0112 upper chamber bowl gasket centrifugation chamber bottom gasket sliding piston upper seal sliding piston lower seal Fuel Systems
C The force developed by the liquid within space "J" of the device shown in the illustration depends upon __________. Illustration MO-0112 the speed of the bowl and the condition of seal "H" the angular velocity at which the liquid travels the speed of the bowl and the condition of seal "U" inertia forces during starting and stopping Fuel Systems
A During normal operation, the liquid retained in space 'J' of the device shown in the illustration is __________. Illustration MO-0112 directly forcing the sliding piston upward to keep the bowl closed maintaining the bowl oil-water seal interface lubricating the shaft bearings maintaining oil pump pressure Fuel Systems
D The area indicated by the letter "L" of the device shown in the illustration is properly called the __________. Illustration MO-0112 pre-injection chamber operating water reservoir channeling chamber injection chamber Fuel Systems
D If the separating temperature is to remain constant, what is the relationship between the specific gravity of the oil and the required size of the regulating ring? Illustration MO-0113 For a constant operating temperature, the greater the specific gravity of the oil the larger the regulating ring. The specific gravity of the oil and the size of the regulating ring are related only during the initial design stages of the centrifuge. With oils of greater specific viscosities it is proper to select smaller regulating rings regardless

 of the operating temperatures desired.
The larger sized regulating rings are designed to be used with oils of lower specific gravities. Fuel Systems
D From the graph shown in the illustration, determine the size of the regulating ring required for the proper operation of the fuel oil centrifuge if the fuel oil specific gravity is 0.9 kg/dm3 at 68F, and the separating temperature is 158F __________. Illustration MO-0113 117 mm 104 mm 86 mm 110 mm Fuel Systems
C Using the graph shown in the illustration, the oil being separated has a specific gravity of .87 kg/dm3 at 72.5C. What will be the specific gravity if the temperature is lowered to 40C? Illustration MO-0113 0.872 kg/dm3 0.882 kg/dm3 0.892 kg/dm3 0.902 kg/dm3 Fuel Systems
C From the graph shown in the illustration, if the separating temperature required is to be 167F, and the specific gravity of the oil is .98 kg/dm3 at 59F, what size regulating ring is required? Illustration MO-0113 86 mm 89 mm 92 mm 95 mm Fuel Systems
D The replacement piping for diesel engine high pressure fuel systems must be the same length and diameter as the original piping to __________. avoid unnecessary parts inventory keep torsional vibration constant use existing supports and braces maintain specified injection characteristics Fuel Systems
D Which of the listed types of gasket material should be used on high pressure fuel oil lines on a diesel engine? Fiberglass Sheet asbestos Neoprene Soft copper Fuel Systems
A The diesel engine shown in the illustration has the highest fuel pressure developed in the part labeled __________. Illustration MO-0003 E X Y Z



Fuel Systems
D To minimize corrosion, fuel oil strainer disks, spacers and scraper blades are made of __________. brass copper iron monel metal or stainless steel Fuel Systems
D The purpose of the interlocked three-way valve shown in the illustration is to __________. Illustration MO-0058
recirculate fuel through the heater during warm-up control the rate of fuel oil flow to the engines act as an emergency fuel shut off, regardless of the fuel being used change fuel from heavy to light oil or vice-versa while insuring that oil is returned to the proper day tank Fuel Systems
A For a continuous operation diesel engine, a duplex filter unit would be the best arrangement because __________. changing filter elements would not interrupt engine operation filtering occurs twice in each pass of oil through the system clogging will not occur dropping pressure is half of that through a single filter unit Fuel Systems
B As shown in the illustration, the viscosimeter would be used to directly control the output of which of the following components? Illustration MO-0077 Outflow from HFO day tank. Final heaters. Injector pumps. HFO purifiers. Fuel Systems
C Heavy fuel oil used in the system shown in the illustration, will have the lowest viscosity __________. Illustration MO-0058 in the settling tank at the transfer pump discharge at the main engine fuel oil header in the three-way valve
Fuel Systems
C In pre-treating fuel oil on a motor vessel, what would you consider the most important factor to prevent high temperature corrosion on an engine's combustion components? Recycle the fuel between the settling tank(s) and service tank via centrifuges more than once. Monitor engine(s) exhaust temperatures more closely. Run one centrifuge as a purifier at a reduced rate to minimize water, especially salt water, in
the fuel.
Drain settling tank(s) and service tank more often only. Fuel Systems
A The temperature of the contaminated fuel oil fed to the centrifuge shown in the illustration should be __________. Illustration MO-0012 203F to less than 212F greater than 212F 160F to 180F selected according to the oil's viscosity index Fuel Systems
D The greatest difference between the centrifuge bowl shown in the illustration and that of a tubular bowl, with straight, vertical, interior surfaces, is that the illustrated unit __________. Illustration MO-0012 does not require a discharge ring when operated as a separator rotates at 1000 rpm slower than the old tubular bowl type rotates at 1000 rpm higher than the old tubular bowl type is self desludging Fuel Systems
A In the device shown in the illustration, the component lettered "A" is the __________. Illustration MO-0012 dirty oil input port heavy phase discharge port seal water input port light phase discharge port Fuel Systems
A The device labeled "D", as shown in the illustration, is the bowl __________. Illustration MO-0112 top hood hub cover Fuel Systems
C The area indicated by the letter "W", shown in the illustration is correctly termed the __________. Illustration MO-0112 upper sliding piston chamber closing chamber opening chamber parting chamber Fuel Systems
D What terminates the sludge discharge cycle of the device shown in the illustration? Illustration MO-0112 The solenoid valve opens, directs high pressure fluid into the closing chamber, and results in an upward movement of the sliding piston. The solenoid valve closes, reduces the water pressure to the paring chamber, and allows the spring force to move the sliding piston upward. The solenoid valve closes, allows the weight of the sliding piston to oppose the low water pressure, and moves it along the axis of the spindle. The solenoid valve closes, allows the water in the opening chamber to bleed off through "S", and the sliding piston moves upward due to the force developed in area "J". Fuel Systems
D Which of the following precautions should be taken prior to starting the separator shown in the illustration? Illustration MO-0127 Check for the correct oil level in the gear housing. Make sure the separator is properly assembled. Release the bowl brake and confirm proper valve line up. All of the above. Fuel Systems
D Which of the following statements is accurate concerning the vibration sensing device used with the separator shown in the illustration? Illustration MO-0127 The vibration switch is sensitive to vibration in a direction horizontal to its mounting base and is normally installed low on the separator where movement is magnified. Vibration sensors are not used with centrifuges currently installed on diesel vessels due to excessive vibrations developed by the main propulsion units. The detector is so arranged to prevent abnormal harmonic frequencies from being developed while the separator is passing through its critical speed range. The detector mechanism consists of an armature suspended on a flexure pivot and restrained from motion by a permanent magnet acting through a small air gap. Fuel Systems
C How may water be removed from the bowl of the separator as shown in the illustration? Illustration MO-0127 The separator is used to remove solids from the processed liquid, therefore the accumulation of water does not present a problem. Water may only be removed from the bowl when the unit is secured and the bowl hood is removed. The water may be removed through the water drain valve or through the sludge ports during the sludge discharge cycle. When the unit is secured and the bowl stops rotating, the water is drained off the bottom of the bowl through orifice ports. Fuel Systems
D Heavy fuel oil used in the system shown in the illustration, will have the lowest viscosity __________. Illustration MO-0058 at the transfer pump discharge in the settling tank in the three-way valve at the main engine fuel oil header Fuel Systems
B The purpose of the interlocked three-way valve shown in the illustration is to __________. Illustration MO-0058
control the rate of fuel oil flow to the engines change fuel from heavy to light oil or vice-versa while insuring that oil is returned to the proper day tank act as an emergency fuel shut off, regardless of the fuel being used recirculate fuel through the heater during warm-up Fuel Systems
B When changing over from residual to distillate fuel on a slow-speed diesel main engine, what is a good guideline to follow regarding the change over? Change over time should not be less than six hours. Rate of temperature change of fuel to the engine should not exceed 2 degrees C per minute. Change over should be accomplished as quickly as possible as dictated by engine load. Change over time should not exceed two hours. Fuel Systems
A When changing over from residual to distillate fuel on a slow-speed diesel propelled vessel, you should limit the rate of temperature change of the fuel in order to prevent what operational difficulty? Seizing and scuffing of fuel pump plungers and injector needle valves due to thermal effects on close clearance components. Dezincafication of the fuel in the mixing tank. Surging/hunting of the governor due to rack sticking. Carbonization in the fuel heater. Fuel Systems
B If the separating temperature is to remain constant, what is the relationship between the specific gravity of the oil and the required size of the regulating ring? Illustration MO-0113 For a constant operating temperature, the greater the specific gravity of the oil the larger the
regulating ring.
The larger sized regulating rings are designed to be used with oils of lower specific gravities. The specific gravity of the oil and the size of the regulating ring are related only during the initial design stages of the centrifuge. With oils of greater specific viscosities it is proper to select smaller regulating rings regardless of the operating temperatures desired. Fuel Systems
D From the graph shown in the illustration, determine the size of the regulating ring required for the proper operation of the fuel oil centrifuge if the fuel oil specific gravity is 0.9 kg/dm3 at 68F, and the separating temperature is 158F __________. Illustration MO-0113 86 mm 117 mm 104 mm 110 mm Fuel Systems
B Using the graph shown in the illustration, the oil being separated has a specific gravity of .87 kg/dm3 at 72.5C. What will be the specific gravity if the temperature is lowered to 40C? Illustration MO-0113 0.902 kg/dm3 0.892 kg/dm3 0.882 kg/dm3 0.872 kg/dm3 Fuel Systems
B From the graph shown in the illustration, if the separating temperature required is to be 167F, and the specific gravity of the oil is .98 kg/dm3 at 59F, what size regulating ring is required? Illustration MO-0113 86 mm 92 mm 89 mm 95 mm Fuel Systems
D After removing the bowl hood of the device shown in the illustration, excessive quantities of sludge are visible. Which of the following statements represents the approach to rectify the situation? Illustration MO-0112 Remove only the disc stack, separate all the discs, clean with steel wool and solvent, replace the disc stack ensuring it is located by use of the dowel pin shown. Disassemble the entire unit, clean all components, replace all defective discs and use the proper lubricant where required. Steam clean the components in place, check for proper alignment, using the match marks provided, reassemble and restart the unit. Disassemble the entire unit, clean all components, replace any defective gaskets and use the proper lubricants where required. Fuel Systems
C When tightening the lock ring "G" of the device shown in the illustration, two events are simultaneously accomplished. Which of the following statements represents these events? Illustration MO-0112 The lock ring insures proper contact between the bowl top and the sliding bowl bottom, in addition to compressing the disc stack. The lock ring forces the disc stack onto the spindle, providing a positive means of rotation and locating the bowl top to seal the separation chamber. When tightened, the lock ring allows for movement of the sliding piston and positions the sliding piston within the bowl bottom. The lock ring insures proper positioning of the disc stack and maintains a positive contact of the bowl top and bowl bottom. Fuel Systems
D Which of the following conditions would be the most probable cause for the 'low oil temperature after preheater' LED indicators, as shown in the illustration, to be illuminated? Illustration MO-0127 Too high a temperature in settling tank. Improper steam trap selection. Too low a temperature in day tank. Incorrect steam control valve setting. Fuel Systems
B On a slow-speed diesel engine vessel equipped with an ALCAP fuel oil purification system, what would be a symptom of an opening solenoid valve leaking by? An increase in RPM. An increase in the rate at which the purifier sludge tank is rising. An increased in the voltage at the EPC control cabinet. An increased amperage draw. Fuel Systems
C Your ship is equipped with ALCAP heavy fuel oil purifiers. The watchstander reports excessive water drained from the fuel oil service tank. Which component should he check? The water transducer located in the dirty oil supply line. The bowl RPM. The water transducer located in the clean oil discharge line. The closing water solenoid valve in the fresh water line. Fuel Systems
B As shown in the illustration, which of the following conditions would be responsible for a "low pressure in oil outlet" alarm to be indicated? Illustration MO-0127 Controller set point changed Throughput too low Emergency stop button not reset Separating temperature too low Fuel Systems
B If item "F" begins leaking during operation, which of the following operating conditions will NOT occur? Illustration MO-0112 The unit will not properly operate and should automatically shut down. The oil/water interface will remain in the same neutral position. The oil/water interface will move outward from the vertical axis of the machine. The water seal will be lost. Fuel Systems
A While operating the fuel oil centrifuge shown in the illustration, the bowl fails to open for sludge ejection. The probable cause is that __________. Illustration MO-0012 the seal ring on the operating slide is defective the operating water pressure is too high the bowl disk set is clogged one or more of the sludge ports is partially clogged Fuel Systems
C When reassembling the bowl of the centrifuge, shown in the illustration, the alignment mark on the locking ring passes the bowl cover mark in excess of the manufacturer's specifications. This is due to __________. Illustration MO-0012 the paring devices have been reinstalled in the wrong order too many disks being left out of the bowl during reassembly excessive wear of the locking ring and/or bowl threads the disks have not been placed back in the bowl in numerical sequence Fuel Systems
B While operating the fuel oil centrifuge shown in the illustration, the fuel oil is being continuously ejected with the sludge and the seal water. The probable cause is the __________. Illustration MO-0012 gravity disk inside diameter is too small gravity disk inside diameter is too large back pressure is too low incorrect number of disks have been place in the disk stack Fuel Systems
C If the bowl of a disk type centrifugal purifier when operated as a separator is not primed, the __________. purifier will act as a clarifier at the discharge ring oil solids will be deposited only at the intermediate top disk oil will be lost through the water discharge ports oil has a tendency to emulsify in the bowl Fuel Systems
A Which of the following statements describes what will occur if the annular spaces, indicated by the letter "K" of the device shown in the illustration, became restricted? Illustration MO0112 The bowl will fail to close when starting and the unit will not shoot when operating. The unit will not start due to pressure/time delay relays. The bowl will fail to close, but the unit will be capable of shooting while in operation. Operating water will be supplied through port "S". Fuel Systems
A As Chief Engineer of a slow speed diesel engine vessel equipped with an ALCAP fuel oil purification system. You note a definite increase in the rate at which the purifier sludge tank is rising. One of the first items to check on your system would be which of the following? The opening water solenoid for leak through. The water transducer located in the dirty oil supply line. The RPM of the bowl. The voltage to the EPC control cabinet. Fuel Systems
D During the change over period from residual to distillate fuel the final fuel filters clog at a decreasing time interval. What is the most likely cause? Gasification of the fuel in the fuel heater. Carbonization of the cylinder oil. Stratification of the fuel in the mixing tank. Incompatibility of the fuels resulting in asphaltenes of the residual fuel precipitating out. Fuel Systems
B What operational difficulties are associated with fuel incompatibility? Reduced rack settings. Frequent clogging of final fuel filters and sticking/scuffing of fuel pump plungers and nozzles. Carbonization of the cylinder oil.  Gasification of the fuel in the fuel heater. Fuel Systems
D The principal hazard to personnel when using a diesel engine fuel nozzle tester is __________. electrical shock toxic fumes explosion blood poisoning Fuel Systems
B An immediate repair is required if a leak occurs in the high pressure fuel piping between the injection pump and fuel nozzle because of the __________. high cost of fuel serious fire hazard pollution hazard poor combustion which will occur in that cylinder Fuel Systems
C Diesel engines are classified as reciprocating internal combustion engines because they __________. use energy from fuel burned outside their cylinders burn fuel in a combustion chamber that moves back and forth burn fuel in a closed chamber which imparts linear motion to pistons use a continuous combustion process to impart rotary motion to the pistons Fundamentals
B The bore of a diesel engine cylinder describes the __________. swept volume of the cylinder inside diameter of the cylinder piston displacement in the cylinder length of the piston stroke Fundamentals
D The cubic inch (or liter) displacement of a cylinder is determined by the diameter of the piston and the __________. length of the crankshaft volume of the clearance space weight of the piston length of the stroke Fundamentals
B The compression ratio of a diesel engine refers to the ratio between the __________. piston area to connecting rod length cylinder volumes at top dead center and at bottom dead center engine cylinder size to piston size the number of compression strokes for a given horsepower Fundamentals
D If the compression ratio is increased on any diesel engine, __________. the expansion ratio will decrease combustion will be slowed down thermal efficiency will decrease thermal efficiency will increase Fundamentals
B The theoretical minimum compression ratio necessary to ensure compression ignition in a direct injection diesel engine is __________. 10 : 1 12 : 1 16 : 1 20 : 1 Fundamentals
A Which of the following relationships exists between the temperatures developed in a combustion space, and the compression ratio of the engine? Higher compression ratios create higher temperature. Higher temperatures create higher compression ratios. Lower temperatures create higher compression ratios. Higher compression ratios create lower temperatures. Fundamentals
B The ratio of the brake horsepower to the indicated horsepower of a diesel engine is its __________. thermal efficiency mechanical efficiency brake thermal efficiency volumetric efficiency Fundamentals
B The most important factor in engine performance is the actual power output at the end of the crankshaft available for doing work. This is known as __________. indicated horsepower brake horsepower net horsepower friction horsepower Fundamentals
B The average pressure exerted on a piston during each power stroke is termed __________. indicated horsepower mean effective pressure exhaust back pressure compression pressure Fundamentals
D The thermal energy produced by an internal combustion engine is transformed into __________. combustion energy internal energy external energy mechanical energy Fundamentals
B What determines the number of events occurring in a cycle of operation in an internal combustion engine? Crankshaft revolution Method of air charging a cylinder and expelling exhaust gases Distance a piston travels during a stroke Number of pistons Fundamentals
A In describing engine operation, what does the term "cycle" mean? The sequence of events that produce a power pulse. One rotation of the engine crankshaft. One stroke of a piston. All of the above. Fundamentals
C The highest pressure in a diesel engine cylinder normally occurs __________. at TDC before TDC after TDC during air starting Fundamentals
C Modern marine diesel engines equipped with mechanical fuel injection operate on a combustion cycle which is __________. entirely constant volume entirely constant pressure a combination of constant volume and constant pressure a combination of constant temperature and constant pressure Fundamentals
A The load is always placed on the lower half of the main bearings in a/an __________. two-stroke/cycle engine four-stroke/cycle engine reverse cycle engine double acting engine Fundamentals
B The camshaft drive is designed to maintain proper camshaft speed relative to crankshaft speed. In maintaining this relationship, the camshaft drive causes the camshaft to rotate at __________. one-half crankshaft speed in a two-stroke cycle diesel engine crankshaft speed in a two-stroke cycle diesel engine two times crankshaft speed in a two-stroke cycle diesel engine one-fourth times crankshaft speed in a four-stroke cycle diesel engine Fundamentals
B Which of the terms listed below represents the operational speed at which excessive engine vibration is created? Non-harmonic speed. Critical speed. Maximum speed. Design maximum speed. Fundamentals
A Most practical diesel engines today operate on a cycle which is a combination of the Diesel and Otto cycles. In this process, compression ignition __________. begins on a constant volume basis begins on a constant pressure basis ends on a constant volume basis begins and ends on a constant volume basis Fundamentals
B The pressure-volume diagrams illustrated are of four internal combustion engine cycles. Which one represents the theoretical diesel cycle? Illustration MO-0102 A B C D Fundamentals
B If point #1 in the diagram shown is the beginning of gas compression, which of the cycles listed is being illustrated? Illustration MO-0036 Otto Diesel Gas Turbine Rankine Fundamentals
A When calculating the indicated power developed in a diesel engine cylinder, 1 horsepower is equivalent to '33,000 foot-pounds per minute'. What conversion factor would be used if the values are based on metric 'kilogram-meters per minute'? 4500 kg-meters per minute = 1 HP 5500 kg-meters per minute = 1 HP 11000 kg-meters per minute = 1 HP 16500 kg-meters per minute = 1 HP Fundamentals
B What is the average piston speed of a five cylinder low-speed engine with a bore of 29.5 inches (75 cm), a stroke of 63 inches (160 cm), and a rated speed of 123 RPM? 645 ft/min (196 m/min) 1291 ft/min (393 m/min) 2582 ft/min (787 m/min) 7749 ft/min (2362 m/min) Fundamentals
A A diesel engine indicator diagram has an area of 22 cm2 and a length of 12.5 cm. If the scale of the indicator spring is 1 mm = 1 kg/cm2, what is the cylinder mean effective pressure? 17.6 kg/cm2 27.5 kg/cm2 34.5 kg/cm2 36.0 kg/cm2 Fundamentals
C A six cylinder, two stroke/cycle diesel engine is 83% efficient and has a cylinder constant of 0.998 while operating with a mean effective pressure of 15 kg/cm2 at a speed of 100 RPM. What is the metric brake horse power developed? 5,559 mbhp 6,698 mbhp 7,455 mbhp 8,982 mbhp Fundamentals
B An eight cylinder, four stroke/cycle, single acting diesel engine has a 650 mm bore and a 1400 mm stroke. What will be the developed indicated metric horsepower if the average mean effective pressure is 30 kg/cm2 at a speed of 100 RPM? 1689 kW 9,111 kW 12,388 kW 24,776 kW Fundamentals
B The speed of the camshaft in a two-stroke/cycle diesel engine, running at 950 RPM, is __________. 475 RPM 950 RPM 1900 RPM 2400 RPM Fundamentals
A A diesel engine cylinder has a swept volume of 125 cubic inches and a compression ratio of 13.5 to 1. What is the clearance volume in the cylinder at top dead center? 10 cubic inches 12.5 cubic inches 13.5 cubic inches 14 cubic inches Fundamentals
B If the piston stroke in a four stroke cycle diesel engine is 10 1/2 inches and the speed of rotation of the crankshaft is 720 RPM, what is the average piston speed? 1200 feet/minute 1260 feet/minute 1320 feet/minute 1380 feet/minute Fundamentals
A A four cylinder, four stroke/cycle, single acting diesel engine has a 740 mm bore and a 1500 mm stroke. What indicated power will be developed if the average mean effective pressure is 18 kg/cm2 at a speed of 90 RPM? 3416 kW
 o
4644 kW
 o
7296 kW
 o
9290 kW Fundamentals
B Line "P" in the illustration is the __________. Illustration MO-0126 line of maximum horsepower propeller curve
line of maximum efficiency
exponential line Fundamentals
D Which of the following conditions will cause the engine to operate in area "A" of the diagram shown in the illustration? Illustration MO-0126 Fouled hull
Damaged propeller blades Inclement weather Excessive propeller cavitation Fundamentals
C The diagram shown in the illustration may be used to determine the proper operation of the engine. Which of the following statements represents an accurate interpretation of the diagram? Illustration MO-0126
The engine may be operated in any area of the diagram provided steps are taken to reposition the load indicator. Operation within area "B" is permitted for extended time periods provided no changes are made to the air intake system. Ideally the engine should be operated in area "A", however, it is permissible to intermittently operate the engine in area "B".
Assuming the load indicator reads 90% and the engine speed is at 80% the engine can be operated until maintenance requirements become apparent.



National Maritime Center Assistant Engineer-DDE
.
13. (2.3.1.6-4) Which of the following conditions would NOT be considered a valid reason for the diesel engine to operate in the area indicated by letter "B" shown in the illustration? Illustration MO-0126
Fundamentals
D Which of the following conditions would NOT be considered a valid reason for the diesel engine to operate in the area indicated by letter "B" shown in the illustration? Illustration MO-0126
Operating the vessel in shallow water
Operating with a fouled or damaged propeller Operating the vessel against high winds and current Operating with minimal hull drag and under light draft Fundamentals
D In the pressure-volume diagram shown in the illustration, fuel injection occurs at point __________. Illustration MO-0035 e d f c Fundamentals
D An indicator card or pressure-volume diagram, shows graphically the __________. compression ratio of the engine volume of the engine relationships between pressure and temperature during one stroke of the engine relationships between pressure and volume during one cycle of the engine Fundamentals
A The indicator card shown in the illustration is produced with a/an __________. Illustration MO-0108 rotating drum sliding camshaft oscillating drum balanced-diaphragm indicator Fundamentals
D On the indicator card shown in the illustration, lines 'A' and 'B' indicate __________. Illustration MO-0108 the end of ignition bottom dead center the end of injection top dead center Fundamentals
C In the pressure-volume diagram, shown in the illustration, what occurs between points "e" and "f"? Illustration MO-0035 The exhaust valve closes. The intake ports close. Pressure in the cylinder decreases. Volume in the cylinder decreases. Fundamentals
C In the pressure-volume diagram, shown in the illustration, the volume line is divided into 16 units indicating __________. Illustration MO-0035 a cylinder volume of 166 cubic inches compression pressure is 1600 PSI a 16 to 1 compression ratio 16 of crankshaft motion between lines A and B Fundamentals
A In the pressure-volume diagram shown in the illustration, curve 'A-d' indicates __________. Illustration MO-0035 combustion at approximately constant pressure opening of exhaust valves fuel injection after dribble start of fuel injection Fundamentals
A In the pressure-volume diagram, shown in the illustration, what is indicated to have occurred by the line connecting points 'd' and 'e'? Illustration MO-0035 The combustion gases have expanded. The crankshaft has rotated 90. Pressure and volume have increased. The fuel/air charge is compressed. Fundamentals
A On the cylinder indicator diagram illustrated, the dotted line indicated as "L" is describing the __________. Illustration MO-0033 cylinder pressure without injection firing pressure at 90 degrees crank angle beginning of compression power expansion curve Fundamentals
A Which of the indicator diagrams illustrated depicts the condition that should be corrected by retarding only the timing? Illustration MO-0029 A B C D Fundamentals
A On the indicator card shown in the illustration, lines 'A' and 'B' indicate __________. Illustration MO-0108 top dead center bottom dead center the end of injection the end of ignition Fundamentals
D In the starting process of a diesel engine, the main object is to attain the compression conditions sufficient to __________. turn the flywheel reduce friction overcome inertia ignite the fuel Fundamentals
D In a diesel engine, after ignition of the fuel occurs, but before the piston reaches TDC, there is little change in the cylinder __________. temperature pressure energy volume Fundamentals
C Turbulence of the compressed air charge in a diesel engine cylinder increases __________. ignition lag piston side thrust the efficiency of fuel combustion compression pressure Fundamentals
A The greatest turbulence in a diesel engine cylinder is created by the __________. shape of the combustion chamber fuel injection spray pattern cylinder swept volume degree of penetration of the fuel oil droplets Fundamentals
C The main operating characteristic of diesel engines which distinguishes them from other internal combustion engines is the __________. method of supplying air cooling system method of igniting fuel valve operating mechanism Fundamentals
B Heat for igniting the fuel oil in the cylinder of a diesel engine is generated by the __________. electronic ignition system compression of air by the piston
friction in the fuel injector
fuel oil heating system Fundamentals
C The formation of carbon monoxide in diesel exhaust gases is reduced by __________. spraying water into the exhaust pipe keeping the exhaust system free of carbon deposits maintaining proper combustion and scavenging avoiding light load operation Fundamentals
D Theoretical perfect combustion in a diesel engine yields by-products of __________. aldehydes and carbon dioxide water vapor and carbon monoxide nitrogen and carbon monoxide water vapor and carbon dioxide Fundamentals
D The minimum speed an engine must attain before ignition can occur depends upon __________. the type and size of the engine
 o
the condition of the engine ambient temperature All of the above. Fundamentals
B Maintaining the proper fuel oil temperature will result in __________. the elimination of valve wear improved atomization a decrease in cylinder blow-by a decrease in cylinder mean effective pressure Fundamentals
D What is the term given to the process of breaking up fuel oil into very fine particles for better combustion? Settling Straining Spraying Atomizing Fundamentals
B Proper atomization of fuel in diesel engine combustion chambers will __________. affect the injection pressure improve combustion reduce compression pressure decrease power output Fundamentals
B Fuel oil penetration into the cylinder of a diesel engine is __________. dependent on air turbulence reduced by finer atomization increased by finer atomization nonexistent in the precombustion chamber system Fundamentals
C Fuel droplets injected into a diesel engine cylinder must have adequate penetration to __________. prolong the ignition delay period ensure the beginning of fuel injection thoroughly utilize the air charge allow controlled fuel combustion Fundamentals
A A diesel engine operating at a light load, when compared to operating at heavy load has an air/fuel ratio that is __________. higher lower equal directly proportional Fundamentals
B As engine RPM is increased from idle speed to full load speed, which of the conditions listed will decrease? Compression ratio Air/Fuel ratio Compression pressure Lube oil pressure Fundamentals
C According to the diagram shown in the illustration, the lube oil system can best be described as a __________. Illustration MO-0007 bypass system dry sump system wet sump system shunt system Lubrication Systems
D On most modern diesel engines, the main and connecting rod bearings receive their lubricating oil by __________. banjo feed splash feed gravity feed pressure feed Lubrication Systems
D A well-lubricated bearing surface always appears __________. well knurled slightly streaked lightly glazed highly polished Lubrication Systems
A Proper lubrication of the main bearings is more easily obtained in a single acting fourstroke/cycle diesel engine than in a single acting two-stroke/cycle diesel engine because __________. bearing pressure in a four-stroke/cycle single acting diesel engine is continually reversed bearing pressure in a two-stroke/cycle single acting diesel engine is continually reversed the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engine two-stroke/cycle diesel engines require more complicated lubrication piping Lubrication Systems
C Lube oil filters remove contaminants more efficiently if the oil being filtered is __________. under high pressure under low pressure heated to reduce viscosity cooled to increase viscosity Lubrication Systems
C Which of the following should always be checked prior to starting a diesel engine? Air filters Fuel oil strainers Crankcase oil level Pyrometer readings Lubrication Systems
C Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started? Exhaust temperature Lube oil level Lube oil pressure Water level in the expansion tank Lubrication Systems
C The most crucial time for any bearing with regards to diesel engine lubrication is __________. during periods of low load during first warm up during initial starting after load reversals Lubrication Systems
D In a normally operating diesel engine, the main source of lubricating oil contamination in the crankcase is a result of the __________. metal particles loosened by wear air when no air cleaners are used condensation of water vapors combustion byproducts removed from the cylinder walls Lubrication Systems
C Before starting a diesel engine that has an engine driven lube oil pump, the operator should __________. open the bypass line cut in the lube oil cooler pressurize the lube oil system with the prelube pump top off the expansion tank Lubrication Systems
C How often should the lubricating oil of a diesel engine be changed? After every trip Every 4000 hours According to manufacturer's instructions Every time they are shutdown Lubrication Systems
C Which of the following devices is normally provided to prevent oil starvation in a diesel engine lubrication system utilizing the 'full flow' principle? Duplex strainer Three-way valve Pressure relief bypass line around the filter Mechanical straining filter Lubrication Systems
D The lube oil pump used in a diesel engine is normally a __________. volute pump centrifugal pump diaphragm pump gear pump Lubrication Systems
A A diesel engine exposed to widely varying ambient temperatures should use a lubricating oil with __________. a high viscosity index a low viscosity index extreme pressure additives no additives Lubrication Systems
D Two important considerations for the proper lubrication of a diesel engine include, the delivery of the oil in sufficient amount, and the __________. cetane number pour point viscosity temperature quality of the oil Lubrication Systems
D A diesel engine should use which type of lubricating oil? Low viscosity Cutting oil High grade vegetable oil Detergent oil Lubrication Systems
A The highest indicated lube oil pressure in a diesel engine should be expected when the engine oil is __________. cold at idle warm at idle warm at full speed warm at full speed and no fuel dilution exists Lubrication Systems
C The TBN value of diesel engine lube oil refers to its ability to __________. resist changes in viscosity with changes in temperature resist emulsification neutralize acids resist oxidation at high temperatures Lubrication Systems
C Which lubricating oil additive is used in diesel engines to reduce the tendency for sludge and varnish to form on the engine parts? Flash point improvers Pour point improvers Inhibitors Foam suppressors Lubrication Systems
C A spring-loaded relief valve is located on some lube oil filters in full flow systems to __________. prevent over pressurization of the filter cartridge prevent over pressurization of the filter casing bypass the filter should it become clogged limit the lube oil outlet pressure Lubrication Systems
D The lube oil strainer shown in the illustration is used on the reduction gear of a mid-size diesel engine. The strainer elements consist of __________. Illustration MO-0057 pleated paper wire mesh fibrous braid metal disks Lubrication Systems
C Most large main propulsion diesel engines use a duplex lube oil strainer to __________. decrease the time required between cleanings remove all large and small foreign objects ensure a positive flow of oil at all times ensure that all lube oil has been treated twice Lubrication Systems
C A magnetic strainer is primarily used in diesel engine reduction gear oil systems to remove small particles of __________. copper Babbitt ferrous materials acidic materials Lubrication Systems
D Where would a coarse screen wire-mesh strainer normally be found on a diesel engine lubrication system? pump discharge line gravity tank inlet line filter bypass return line pump suction line Lubrication Systems
C How is the illustrated strainer element cleaned during engine operation? Illustration MO-0057 The drain plug is removed and the housing is drained. The housing is removed and the element is cleaned with a solvent. The T-handle is rotated. The strainer element is removed, cleaned in kerosene or solvent, and dried with an air brush. Lubrication Systems
C What type of engine lubrication oil filter system sends filtered oil directly to the high pressure supply gallery? centrifugal purifier system bypass system shunt system batch system Lubrication Systems
C In a by-pass type lubrication system for a diesel engine, the dirty oil line to the filter should be taken from the___________. lube oil pump suction line lube oil pump discharge line bottom of the lube oil sump outlet from the lube oil header Lubrication Systems
D Maximum lube system operating pressure for a diesel engine is normally regulated by a/an __________. orifice in the pump suction special filter design pressure drop through the filter relief valve Lubrication Systems
A The lube oil cooler is located after the lube oil filter in order for __________. the filter to operate more efficiently the lube oil cooler to be bypassed positive lube oil pump suction to be assured galvanic action in the cooler to be minimized Lubrication Systems
C Which of the following statements is true concerning a main diesel engine oil cooler? The oil temperature is less than the cooling water temperature. The oil pressure is less than the cooling water pressure. The oil pressure is greater than the cooling water pressure. The oil flow control valve is always installed in the oil input line. Lubrication Systems
D Heat exchangers are most commonly found in a small auxiliary diesel engine __________. fuel oil system governing system air starting system lube oil system Lubrication Systems
B Reduction gear lube oil temperatures for keel cooler installations are generally __________. lower than raw water cooled installations higher than raw water cooled installations identical to raw water cooled installations lower than raw water cooled installations, but the pressure will be higher Lubrication Systems
C One advantage of a vacuum feed sight glass indicator used on cylinder lubricators over the discharge side liquid filled type sight glass is __________. there are fewer moving parts adjustments are not required better visual metering adjustment a lower grade of cylinder oil may be used Lubrication Systems
D Mechanical lubricators for diesel engine cylinders are usually small reciprocating pumps which are __________. operated manually once each hour operated until the engine has started placed into operation only at maximum load adjustable to meet lubrication requirements Lubrication Systems
C The rate of cylinder lubricating oil metered to each cylinder of a large, low-speed, main propulsion diesel engine is __________. the same, whether at sea, or during maneuvering adjusted during each hour of operation while at constant RPM reduced during periods of low load operation lower at sea than while maneuvering Lubrication Systems
C The device shown in figure "A" of the illustration is used to __________. Illustration MO-0042 inject fuel into the cylinder admit starting air to the cylinder provide lubrication to the cylinder provide an adapter to obtain combustion pressure readings Lubrication Systems
A The illustrated device is used to __________. Illustration MO-0050 supply cylinder lubricating oil to the engine meter fuel oil to the injectors admit the correct amount of starting air to the cylinders in proper order actuate exhaust valves in the correct sequence Lubrication Systems
C The component labeled as part #20 in the illustration is used to __________. Illustration MO-0050 meter the amount of oil flow to the cylinder lubricating quill adjust the timing of the cylinder lubricating oil to the cylinder indicate the quantity of oil flow to the cylinder prevent the backflow of oil and combustion gases Lubrication Systems
C The adverse effects of burning high sulfur fuel can be compensated for by using a cylinder oil having sufficient __________. dispersant additives floc point depressive additives alkalinity ignition quality Lubrication Systems
A The device shown in the illustration is classified as a/an __________. Illustration MO-0008 comparator type mist detector exhaust gas vapor condenser Ringleman exhaust gas analyzer reflective type explosion meter Lubrication Systems
C The device shown in the illustration is a __________. Illustration MO-0008 rotary type mist detector, designed for use in four-stroke, high speed diesel engines photo-electric, explosive gas indicator, for use in high speed, two-stroke, trunk type piston
 engines
comparator type mist detector for large low speed, crosshead type engines level type explosimeter, for small medium speed, trunk piston type engines Lubrication Systems
A The purpose of an oil mist detector in a main propulsion diesel engine is to warn of __________. a possible overheated bearing excessively high crankcase vacuum low cylinder oil pressure excessive carbon buildup in the lube oil Lubrication Systems
D Which of the following problems could develop due to the accumulation of oil vapors in the crankcase of a diesel engine? Reduced lubrication Poor fuel economy Combustion knock Crankcase explosion Lubrication Systems
D Crankcase explosions in propulsion diesel engines result from __________. the splashing of lubrication oil by the crankshaft the dilution of crankcase oil with particles of combustion broken fuel lines spraying oil on the crankcase the ignition of unburned fuel and air in the crankcase Lubrication Systems
A For diesel engine piston cooling, lubricating oil can be supplied to the pistons by a/an __________. oil spray oil wick oil control rings drilled passage through the camshaft Lubrication Systems
D Shaker, circulation, and spray are the three general methods used in __________. pre-injection fuel oil treatment lube oil filtration lube oil purification piston cooling Lubrication Systems
A The upper piston rings in large, slow-speed, two-stroke/ cycle diesel engines are most effectively lubricated by oil __________. fed from mechanical lubricators thrown off from the main bearings supplied from wick fed drip lubricators flow from a centrifugal or banjo oiler Lubrication Systems
D Wristpin bearings are difficult to lubricate because of their oscillating motion and __________. their free-floating design their relatively small size the reciprocating motion of the piston their position in the lubrication system Lubrication Systems
C A 'Blotter test' is a test performed on the lube oil of a diesel engine which can determine __________. the specific gravity of the oil the flash point of the oil a change in the oils viscosity the TBN number of the oil Lubrication Systems
B Which of the following test indicators should be considered the most significant factor in determining as to whether or not a diesel generator's lube oil should be drained and renewed? The oil appears black in color. An extremely high neutralization number. An extremely low precipitation number. An increase in flash point. Lubrication Systems
C If the analysis of used lube oil indicates a high content of iron particles, this could indicate __________. corrosive deterioration of a bearing inadequate air filtration excessive ring and liner wear excessive cooling of lubricating oil Lubrication Systems
C A decrease in the flash point of diesel engine lube oil indicates the lube oil has become __________. contaminated with sludge contaminated with carbon diluted with fuel oil diluted with water Lubrication Systems
A What type of engine lubrication oil filter system sends filtered oil directly to the high pressure supply gallery? shunt system batch system centrifugal purifier system bypass system Lubrication Systems
A In a by-pass type lubrication system for a diesel engine, the dirty oil line to the filter should be taken from the___________. bottom of the lube oil sump lube oil pump discharge line lube oil pump suction line outlet from the lube oil header Lubrication Systems
A The device shown in the illustration is classified as a/an __________. Illustration MO-0008 comparator type mist detector Ringleman exhaust gas analyzer reflective type explosion meter exhaust gas vapor condenser Lubrication Systems
C The device shown in the illustration is a __________. Illustration MO-0008 level type explosimeter, for small medium speed, trunk piston type engines rotary type mist detector, designed for use in four-stroke, high speed diesel engines comparator type mist detector for large low speed, crosshead type engines photo-electric, explosive gas indicator, for use in high speed, two-stroke, trunk type piston engines Lubrication Systems
A The purpose of an oil mist detector in a main propulsion diesel engine is to warn of __________. a possible overheated bearing low cylinder oil pressure excessively high crankcase vacuum excessive carbon buildup in the lube oil Lubrication Systems
C Which of the following problems could develop due to the accumulation of oil vapors in the crankcase of a diesel engine? Poor fuel economy Combustion knock Crankcase explosion Reduced lubrication Lubrication Systems
C One advantage of a vacuum feed sight glass indicator used on cylinder lubricators over the discharge side liquid filled type sight glass is __________. a lower grade of cylinder oil may be used adjustments are not required better visual metering adjustment there are fewer moving parts Lubrication Systems
B Mechanical lubricators for diesel engine cylinders are usually small reciprocating pumps which are __________. operated manually once each hour adjustable to meet lubrication requirements placed into operation only at maximum load operated until the engine has started Lubrication Systems
D The rate of cylinder lubricating oil metered to each cylinder of a large, low-speed, main propulsion diesel engine is __________. adjusted during each hour of operation while at constant RPM lower at sea than while maneuvering the same, whether at sea, or during maneuvering reduced during periods of low load operation Lubrication Systems
B The device shown in figure "A" of the illustration is used to __________. Illustration MO-0042 admit starting air to the cylinder provide lubrication to the cylinder inject fuel into the cylinder provide an adapter to obtain combustion pressure readings Lubrication Systems
A The illustrated device is used to __________. Illustration MO-0050 supply cylinder lubricating oil to the engine actuate exhaust valves in the correct sequence meter fuel oil to the injectors admit the correct amount of starting air to the cylinders in proper order Lubrication Systems
A The component labeled as part #20 in the illustration is used to __________. Illustration MO-0050 indicate the quantity of oil flow to the cylinder adjust the timing of the cylinder lubricating oil to the cylinder meter the amount of oil flow to the cylinder lubricating quill prevent the backflow of oil and combustion gases Lubrication Systems
B The adverse effects of burning high sulfur fuel can be compensated for by using a cylinder oil having sufficient __________. ignition quality alkalinity dispersant additives floc point depressive additives Lubrication Systems
D A 'Blotter test' is a test performed on the lube oil of a diesel engine which can determine __________. the flash point of the oil the specific gravity of the oil the TBN number of the oil a change in the oils viscosity Lubrication Systems
A If the analysis of used lube oil indicates a high content of iron particles, this could indicate __________. excessive ring and liner wear inadequate air filtration excessive cooling of lubricating oil corrosive deterioration of a bearing Lubrication Systems
A A decrease in the flash point of diesel engine lube oil indicates the lube oil has become __________. diluted with fuel oil contaminated with sludge diluted with water contaminated with carbon Lubrication Systems
A A bronze bearing liner with a lead-tin flashing has a milky-white color over most of its surface and some areas of exposed bronze. The white coloring indicates __________. water contamination of the lube oil system proper break-in wear improper break-in wear relocation of the overlay flashing Lubrication Systems
A While underway, a slow-speed diesel engine lube oil sump level slowly begins to decrease. Which of the following should be checked? The lubricating oil cooler for leakage into the cooling system. The standby lube oil pump to ensure it is not operating. The tank heating coils to ensure they are secured. The piston oil scraper rings for excessive wear. Lubrication Systems
A What could cause the bypass valve in a full-flow lubrication system to open? Clogged filter element Bypass valve setting is too high Check valve stuck open Fuel dilution of the lubricant Lubrication Systems
D A dirty lube oil strainer can result in __________. excessive oil consumption low lube oil temperature crankcase dilution low bearing oil pressure Lubrication Systems
C Lube oil in the fresh water cooling system of a diesel engine may result from a __________. camshaft seizure lube oil pump failure lube oil cooler failure lube oil sump overflow Lubrication Systems
C Oil oxidation, as a result of excessively high lube oil temperature, is harmful to a diesel engine because __________. lube oil viscosity is always decreased oil foaming will occur corrosive by-products are usually formed large quantities of oil are consumed Lubrication Systems
A Which of the following effects will excessively cold lube oil have on the operation of a diesel engine? The engine will crank slowly and may fail to start. The engine will overspeed when started. The fuel oil supply will become diluted resulting in rough running. The cooling system will overheat causing the engine to stall. Lubrication Systems
C Oil analysis for a crosshead type diesel engine indicates the TBN of the crankcase lubricating oil is increasing. This is most likely associated with which of the following? Excessive purification temperatures Increase in the water content of the crankcase lubricating oil Leaking stuffing boxes introducing cylinder lubricating oil into the crankcase  Bearing wear Lubrication Systems
D Crankcase explosions in propulsion diesel engines result from __________. the splashing of lubrication oil by the crankshaft the dilution of crankcase oil with particles of combustion broken fuel lines spraying oil on the crankcase the ignition of unburned fuel and air in the crankcase Lubrication Systems
A If a diesel engine has been stopped because of piston seizure due to severe overheating, the crankcase __________. inspection covers should not be opened until the engine has cooled ventilation system should be continued in operation for one hour for cooling scavenge pump should be immediately secured to prevent loss of lube oil explosion covers should be opened slightly to provide extra ventilation Lubrication Systems
B For a given fuel, a change in the compression ratio will affect the ignition lag by which of the listed means? An increase in compression ratio will increase the ignition lag. An increase in compression ratio will decrease the ignition lag. A decrease in compression ratio will decrease the ignition lag. A decrease in ignition lag will increase the compression ratio. Main Engines
D The time between injection and ignition of the fuel is known as __________. turbulence lag after burning ratio injection lag ignition delay Main Engines
B When is fuel injected into a cylinder of diesel engines? Before air in the cylinder is compressed. After air in the cylinder is compressed. After combustion gases in the cylinder have expanded. As air is taken into the cylinder. Main Engines
C Which area of the indicator diagram illustrated, indicates the ignition delay period in a diesel engine cylinder? Illustration MO-0033 G H J K Main Engines
A The pressure in an operating diesel engine cylinder continues to rise for a short period after the piston passes top dead center as a result of the __________. expansion during the combustion process exhaust and intake valves just closing maximum compression pressure is just being attained fuel injection occurring at that point and combustion begins Main Engines
C The rate of pressure rise during the period following fuel ignition in a diesel engine is influenced by the length of the ignition delay period and the __________. valve overlap volumetric efficiency turbulence of the air charge fuel efficiency Main Engines
D On the cylinder indicator diagram illustrated, the maximum rise in pressure occurs during the period labeled as __________. Illustration MO-0033 J K G H Main Engines
D Which statement about diesel engine combustion is true? Combustion does not begin until the piston starts down on the power stroke. Maximum combustion pressure is reached before TDC. Turbulence in the cylinder causes a delay in ignition. Maximum cylinder firing pressure is not developed until the piston passes TDC. Main Engines
C Fuel combustion in a diesel engine cylinder should begin just before the piston reaches top dead center and should __________. end when fuel injection has been completed end at bottom dead center continue through the after-burning period be completed exactly at top dead center Main Engines
C On the cylinder indicator diagram illustrated, the dotted line indicated as "L" is describing the __________. Illustration MO-0033 power expansion curve beginning of compression cylinder pressure without injection firing pressure at 90 degrees crank angle Main Engines
C Which area of the indicator diagram illustrated, indicates the afterburning period in a diesel engine cylinder? Illustration MO-0033 J H K G Main Engines
D Item labeled "L" as shown in section 6 of the illustration is identified as the __________. Illustration MO-0025 air filter exhaust manifold non return scavenge valve after cooler Main Engines
B While underway, which of the following would be the FIRST step in reversing a direct reversing large, slow-speed, main propulsion, diesel engine? Manually trip the over speed device. Set the fuel rack to zero. Disengage the safety interlock. Slide the camshaft to the neutral position. Main Engines
C In a large slow-speed propulsion diesel engine, the force applied to the piston is __________. against the crosshead during power stroke and away from the crosshead during the compression stroke
against the crosshead during the compression stroke and away from the crosshead during the
 power stroke
against the crosshead during the power and compression strokes
away from the crosshead during the power and compression strokes Main Engines
D Cast iron pistons used in large propulsion diesel engines are constructed with __________. no taper for the entire length
the skirt being tapered and smaller than the crown the skirt being tapered and larger than the crown the crown being tapered and smaller than the skirt Main Engines
D Which of the following procedures should be carried out when a large, low-speed, diesel engine is operated with one cylinder secured? Lubrication to the defective cylinder should be increased.
 o
Cooling water temperature to the engine should be increased. Only the turbocharger speed should be reduced. Engine speed should be reduced. Main Engines
C In the slow speed diesel engine shown in the illustration, the part labeled "E" is the __________. Illustration MO-0003 high pressure lube oil line low pressure lube oil line high pressure fuel line
low pressure fuel line Main Engines
D During maneuvering operations for a direct reversing large, low-speed, main propulsion diesel engine, which of the following actions is used to stop the shaft from turning prior to changing the engine rotation for a vessel with moderate headway? The way of the vessel Flywheel inertia Securing cylinder lubricators Admission of reversing start air Main Engines
B The line identified as "I" in the illustration is used to __________. Illustration MO-0066 deliver fuel oil to the injector supply lubricating oil for actuating the exhaust valve deliver cooling water to the exhaust valve actuating device exhaust gas and vapors from the power cylinder Main Engines
B Which letter represents the scavenging air system non-return valve in the illustration? Illustration MO-0003 Q P U W Main Engines
D Valve cages are used on some large diesel engines to __________. reduce wear on the valve stem permit the use of alloy valve seat materials reduce heat transfer from the valve seat facilitate valve removal for servicing Main Engines
B In the diesel engine shown in the illustration, the purpose of the part labeled "P" is to __________. Illustration MO-0003 boost the scavenge air pressure ensure one way air flow into the air header provide turbulence in the scavenge air cool the scavenge air Main Engines
A In the illustrated engine, the fuel camshaft gear drive housing is indicated as letter __________. Illustration MO-0003 F Z G B Main Engines
B A diesel engine crankcase ventilation system __________. prevents spark generation removes combustible gases determines the level of combustible gases provides inert gas generation in crankcase Main Engines
A A safety crankcase cover differs from other diesel engine access doors in that it is fitted with a __________. spring-loaded pressure plate hand wheel nut-operated clamp large gasket Main Engines
C The part labeled "X" shown in the illustration is a __________. Illustration MO-0003 fuel line water line lube oil line control linkage Main Engines
D According to the illustration, fuel delivery to the cylinder is terminated and controlled with the component that is identified as the letter __________. Illustration MO-0097 C H K I Main Engines
A Which of the following processes is indicated by the flow arrows shown in the illustration? Illustration MO-0026 Relief of excessively high pressure gases from the cylinder. Cooling water bypass flow to the heat sink. Return flow of excess fuel oil from the injector. Return air flow during start-up upon achieving ignition. Main Engines
A Which of the listed design features is most common with a two-stroke cycle, low-speed main propulsion diesel engine? Piston rod and crosshead construction 90 degree 'V' configuration Double acting trunk type pistons Single reduction gearing Main Engines
A There are two glands provided where the piston rod exits the cylinder shown in the illustration. The purpose of the top gland is to __________. Illustration MO-0083 seal against scavenge air leakage prevent crankcase oil leaking out maintain crankcase vacuum maintain crankcase pressure Main Engines
D The diesel engine shown in the illustration, the exhaust manifold is indicated by the letter __________. Illustration MO-0003 A B P U Main Engines
C The opening of an exhaust valve on a modern, large, low-speed, main propulsion diesel engine, may be actuated by __________. direct action of the overhead cam shaft compressed air pressure hydraulic "push rods" direct action of the main piston moving down Main Engines
B The exhaust ports shown in the illustration are identified with the letter " ". Illustration MO-0003 B Q T U Main Engines
D In a large, slow-speed, main propulsion diesel engine, which of the parts listed is under tension when the engine is running? Bed plate Column Entablature Tie rod Main Engines
B The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by __________. mechanical push rods compressed air pressure hydraulic pressure exhaust gas pressure Main Engines
A The insertion of shims between the foot of a marine type connecting rod and a bearing box would result in __________. increased compression ratio decreased compression ratio increased bearing clearance decreased bearing clearance Main Engines
D In the diesel engine illustrated, what part is under compression when firing is taking place in a particular cylinder? Illustration MO-0003 Tie rod Piston rod nut Lubrication telescopes Piston rod Main Engines
C In the pressure-volume diagram shown in the illustration, the atmospheric pressure line is indicated by line __________. Illustration MO-0035 A B C de Main Engines
A Which of the indicator diagrams illustrated depicts the condition that should be corrected by retarding only the timing? Illustration MO-0029 A B C D Main Engines
D In diesel engines designed with a crosshead, the motion of the piston rod can be described as __________. reciprocating at the crank pin, rotary at the piston pin straight rotation reciprocating at the piston pin, rotary at the crank pin straight reciprocation Main Engines
D Which of the indicator diagrams illustrated indicates the condition that should be corrected by retarding the timing, and the fitting of thicker shims to the connecting rod? Illustration MO-0029 A B C D Main Engines
B In a large slow-speed propulsion diesel engine, the side thrust on the crosshead is the direct result of __________. the piston rod acting against the crosshead during the power stroke the angularity of the connecting rod against the crosshead during the power stroke the velocity of the crankpin during the power stroke cylinder pressure acting against the piston crown Main Engines
D Which of the bearings listed below is most widely used for the main and connecting rod bearings of a modern high-speed diesel engine? Poured Babbitt, self-aligning Split roller Steel-lined Precision insert Main Engines
D Device "E" shown in the illustration is known as the __________. Illustration MO-0122 lube oil manifold extrusion tube assembly over speed trip shaft fuel manifold Main Engines
A The injector rack of the diesel engine shown in the illustration is indicated by the component labeled __________. Illustration MO-0122 "G" "E" "F" "B" Main Engines
C The fuel injector for the diesel engine shown in the illustration, is identified as __________. Illustration MO-0122 "M" "Z" "19" "H" Main Engines
B Which letter represents the exhaust gas exit point for the diesel engine shown in the illustration? Illustration MO-0122 "J" "V" "N" "K" Main Engines
B The diesel engine water inlet jumper illustrated is represented by the letter or number __________. Illustration MO-0122 "W" "M" "N" "14" Main Engines
D The water inlet manifold for the diesel engine shown in the illustration is represented by the letter or number__________. Illustration MO-0122 "W" "M" "13" "N" Main Engines
A The main lube oil manifold, for the diesel engine shown in the illustration, is represented by the letter or number __________. Illustration MO-0122 "O" "N" "17" "11" Main Engines
B Component 'U' of the diesel engine shown in the illustration is called the __________. Illustration MO-0122 frequency tuner crankshaft counterweight
 o
frame stiffener
 o
main bearing support assembly Main Engines
B The diesel engine component labeled "1", shown in the illustration is called a/an __________. Illustration MO-0122 external thread exhaust valve spring
inlet valve spring
conical speed/surge prevention device Main Engines
D The inlet valves for the diesel engine shown in the illustration are indicated by the letter or number __________. Illustration MO-0122 "2"
 o
"H" "19" none of the above are correct Main Engines
D Which of the components listed is only found in an opposed piston engine? Exhaust valves Scavenging ports Combustion chambers Upper and lower crankshafts Main Engines
D The diesel engine component labeled "3", shown in the illustration is called the __________. Illustration MO-0122 scavenging air space cylinder liner head valve assembly cylinder head Main Engines
D The diesel engine component labeled "5", shown in the illustration is known as the __________. Illustration MO-0122 heat sink space
 o
piston crown connecting rod end assembly piston thrust washer Main Engines
A The diesel engine wrist pin in the illustration is indicated by the component labeled __________. Illustration MO-0122 "7" "G" "S" "17" Main Engines
A The diesel engine connecting rods shown in the illustration are distinctively named____________. Illustration MO-0122 fork and blade male and female hook and nail left hand and right hand Main Engines
B What is the function of component "13" shown in the illustration? Illustration MO-0122 The inlet jumper directs cooling water to the cylinder liner. The device delivers the oil for piston cooling, in addition to liner lubrication.
 o
The water pipe is the mechanism in which the 'shaker' method of piston cooling is accomplished.
 o
The sample tube monitors the cylinder for evidence of piston blow by. Main Engines
A Item '17' in the illustration is the dipstick. When should the length of the dipstick be changed? Illustration MO-0122 In most situations this would never be done.
If the operating oil level of the engine is consistently below normal, it will be necessary to use a longer dip stick.
When changing the oil in an operating engine, it may become necessary to use a longer stick to obtain the exact location of the oil level at all times.
If sludge buildup on the bottom of the pan becomes excessive, it will become necessary to shorten the dipstick to accommodate for the false oil level reading. Main Engines
A In a two-stroke/cycle, opposed piston, diesel engine, one crankshaft operates several crank angles in advance of the other crankshaft to __________. allow the exhaust ports to open and close before the inlet ports close allow the scavenge ports to open and close simultaneously with the exhaust ports prevent scavenge air pressure buildup in the cylinders prevent the exhaust piston from reaching TDC and BDC before the intake piston Main Engines
A During the power stroke, the side thrust of a trunk type piston is a result of the angle __________. formed by the connecting rod and the cylinder center line formed by the piston in relation to the piston pin between the crank arm and crankpin between the master and link connecting rods Main Engines
D Which of the listed cylinder head design features is shown in the illustration? Illustration MO-0013 The valve cages are provided for the exhaust valves. The engine is equipped with a dry liner. A gastight seal is provided by a gasket between the cylinder head and cylinder liner. The engine cylinder head is fitted with replaceable valve seats. Main Engines
A Which letter represents the top deck (valve) cover of the engine shown in the illustration? Illustration MO-0122 A' H' 8' None of the above are correct. Main Engines
B Which of the following represents the diesel engine camshaft shown in the illustration and its relative rotating speed? Illustration MO-0122 "B" is the camshaft and it rotates at one half of the crankshaft speed. "B" is the camshaft and its rpm will match that of the flywheel. "T" is the camshaft and its speed equals crankshaft speed. "Y" is the main camshaft drive and rotates at crankshaft speed. Main Engines
C The diesel engine rocker arms shown in the illustration serve to __________. Illustration MO-0122 convert rotational energy to reciprocating pressures operate the exhaust and starting valves open the exhaust valves and operate the unit injectors open the intake and exhaust valves Main Engines
D The rocker arms of the diesel engine shown in the illustration are indicated by __________. Illustration MO-0122 "D" "C" "B" "C" and "Y" Main Engines
A Which of the listed design features is most common with a two-stroke cycle, low-speed main propulsion diesel engine? Piston rod and crosshead construction 90 degree 'V' configuration Double acting trunk type pistons Single reduction gearing Main Engines
A If the speed of the propeller is 135 RPM, the speed of the engine camshaft shown in the illustration will be __________. Illustration MO-0003 135 RPM 270 RPM variable depending on the camshaft gear train gear ratios variable depending on the ratio between engine rpm and propeller shaft rpm Main Engines
B In the illustrated engine, the main camshaft controls the timing of which of the following components? Illustration MO-0003 exhaust valves fuel pumps Intake valves All of the above. Main Engines
B The lower end of the piston rod, shown in the illustration, is fitted into the __________. Illustration MO-0003 crank pin crosshead piston pin crosshead guide Main Engines
B There are two glands provided where the piston rod exits the cylinder shown in the illustration. The purpose of the top gland is to __________. Illustration MO-0083 prevent crankcase oil leaking out seal against scavenge air leakage maintain crankcase vacuum maintain crankcase pressure Main Engines
C The piston rod scraper box incorporated in a two-stroke/cycle, crosshead diesel engine serves to __________. eliminate the necessity for an oil scraper ring prevent side thrust and cylinder scoring prevent sludge and dirty oil from entering the crankcase scrape oil and carbon deposits off the cylinder walls Main Engines
C The item labeled "T" as shown in figure 4 of the illustration is identified as the __________. Illustration MO-0025 after cooler air blower exhaust gas turbine air filter Main Engines
B In what figure of the illustration does the crosshead experience the greatest side thrust? Illustration MO-0025 Figure 1 Figure 2 Figure 6 Figure 5 Main Engines
C Telescopic pipes which are attached to water cooled pistons of large, slow-speed, main propulsion diesel engines are designed to __________. overcome excessive crankcase pressure prevent excessive lube oil temperature allow piston cooling water to efficiently enter the piston despite its reciprocating piston motion without contaminating the engine lube oil prevent contamination of the cylinder cooling water with engine lube oil Main Engines
B High-speed, multi-cylinder, diesel engines commonly use counterweights placed opposite to the crankpins to __________. prevent bearing loads provide dynamic balance by equalizing centrifugal force counteract inertia forces provide a balance of rocking couples around the crankshaft Main Engines
B The diesel engine shown in the illustration utilizes the type of cylinder construction identified as __________. Illustration MO-0007 a dry liner a wet liner integral with a removable sleeve integral with a non- removable sleeve Main Engines
D Why are some diesel engine cylinder liners plated on the wearing surface with porous chromium? The chromium will not wear out the piston rings. The chromium strengthens the liners in the way of the scavenging air ports. Chromium eliminates the need for oil scraper rings. Pores in the plating aid in maintaining the lube oil film. Main Engines
A The lower water seal on a diesel engine wet cylinder liner must allow for liner axial movement. This seal is most commonly a __________. neoprene O-ring soft copper gasket precision ground flange joint flexible metallic seal ring Main Engines
A Which construction detail is apparent in the connecting rod and piston assembly shown in the illustration? Illustration MO-0011 The piston is designed with a heat dam. It is a fork assembly. The piston is water cooled. The wrist pin is free floating. Main Engines
D The illustration shown describes a __________. Illustration MO-0069 four cycle opposed cylinder diesel engine four cycle opposed piston diesel engine two cycle opposed cylinder diesel engine two cycle opposed piston diesel engine Main Engines
D Which of the following statements is correct concerning the connecting rod and piston assembly shown in the illustration? Illustration MO-0011 The piston is free to rotate on the carrier thrust washer. The piston pin is bolted to the connecting rod. The piston has a heat dam. All of the above. Main Engines
D Item #16 of the piston shown in the illustration is a/an __________. Illustration MO-0011 oil drain passage bearing insert tang piston carrier pin thrust plate or thrust washer Main Engines
B Piston cooling fins are located __________. on top of the piston crown underneath the piston crown at the base of the piston skirt inside the cylinder liner cooling water jacket Main Engines
A Ring groove inserts are occasionally used on aluminum alloy pistons to __________. reduce the ring groove wear rate seal against crankcase vapors lessen the wear on aluminum parts of the cylinder allow for the greater expansion rate of aluminum Main Engines
D Which of the following statements would apply when checking the valve clearance of the unit shown in the illustration? Illustration MO-0074 The valve is mechanically adjusted at point "D". The valve is mechanically adjusted at point "E". Tappet clearance is measured between points "A" and "B". Cold valve clearance is measured between components "C" and "D". Main Engines
D When inspecting the valve mechanism shown in the illustration, normal maintenance would include __________. Illustration MO-0074 mechanically adjusting the valve at point "D" mechanically adjusting the valve at point "E" changing the tappet clearance as measured between points "A" and "B" measuring the cold valve clearance between components "C" and "D" Main Engines
A When a naturally aspirated four-stroke/cycle diesel engine is converted for supercharging, which of the following changes must be made to the valve timing? The intake valve opening is advanced and the exhaust valve closing is retarded. The intake valve opening is unchanged and the exhaust valve closing is advanced. The intake valve opening is retarded and the exhaust valve closing is advanced. The intake valve closing is retarded and the exhaust valve closing is advanced. Main Engines
A When a naturally aspirated four-stroke/cycle diesel engine is converted for supercharging, which of the following changes must be made to the valve timing? The intake valve opening is advanced and the exhaust valve closing is retarded. The intake valve opening is unchanged and the exhaust valve closing is advanced. The intake valve opening is retarded and the exhaust valve closing is advanced. The intake valve closing is retarded and the exhaust valve closing is advanced. Main Engines
D After testing your medium-speed engine's exhaust valve springs you find one with a spring constant that is lower than specified by design and a length that is reduced in length from that specified by design. What is the recommended course of action? Anneal spring to restore the spring constant to the original value. Restore the spring to its original length by stretching. Remove shims to restore spring to its original length. Replace spring and check the valves cam and follower for marring caused by bounce. Main Engines
A During main engine performance testing it is noticed that the firing pressure in one cylinder is lower than the average, but cylinder compression pressure and fuel pump delivery rate are normal. Which of the following would most likely be the cause? Late fuel injection Worn piston rings Early fuel injection Low engine load Main Engines
A During main engine performance testing it is noticed that the firing pressure of one cylinder is higher than the average, but cylinder compression pressure is normal. Which of the following would most likely be the cause? Early fuel injection Worn piston rings High engine load Late fuel injection Main Engines
C During main engine performance testing it is noticed that one cylinder has firing and compression pressures lower than average. Which of the following would most likely be the cause? Early fuel injection Low engine load Worn piston rings Late fuel injection Main Engines
B A motor vessel has three centrifuges to pre-treat the fuel which can be configured to operate in series, parallel, and series-parallel. A large quantity of water is determined to be present in the fuel. How would you configure the centrifuges to deal with this problem? Run all three centrifuges as purifiers and decrease throughput. Run two centrifuges in parallel as purifiers discharging to the third one in series as a clarifier. Increase 'shoot' cycles and run two centrifuges in series as purifiers. Drain settling and service tanks more often and run two centrifuges in series, purifier and
clarifier.
Main Engines
D A motor vessel has two centrifuges to pre-treat fuel to the engine(s) which may be
configured to operate in series or parallel. A large quantity of water has been determined to be
present in the fuel. What actions would you take to minimize the effect of water prior to fuel
injection?
Run both centrifuges in series as purifiers and increase 'shoot' cycles. Maintain normal fuel oil throughput through both centrifuges functioning as clarifiers and
increase the 'shoot' cycle of the two clarifiers.
 Drain settling tank(s) and service tank more often only, and monitor reduction in water content  Run first centrifuge as a purifier in series with second as clarifier and reduce throughput and
increase 'shoot' cycles'.
Main Engines
A Low compression pressure in a diesel engine can be caused by __________. improperly seating intake valves leaking cylinder liner seal rings late fuel injection timing carbon deposits on the piston Main Engines
B Oil accumulating in the exhaust piping or manifold of a diesel engine can be caused by __________. collapsed hydraulic valve lifters worn valve guides excessive crankcase vacuum excessive lube oil pressure Main Engines
C When one cylinder has a lower compression pressure and higher exhaust gas temperature than any of the other engine cylinders, which of the conditions listed will be indicated? Advanced ignition Clogged air intake Leaky exhaust valve High exhaust pressure Main Engines
B Excessive wear at part #11, as shown in the illustration, would result in __________. Illustration MO-0027 improper timing increased oil consumption lost compression low oil pressure Main Engines
A If a valve seat insert, similar to that shown in the illustration is cracked, this may be indicated by __________. Illustration MO-0043 white vapor in the exhaust gas high exhaust pyrometer readings on that particular cylinder continuous spring surge a jammed indicator cock Main Engines
C Excessively worn, or polished ends on a diesel engine valve spring, indicate __________. burned exhaust valves excessive spring compression spring surge worn valve seats Main Engines
B Bouncing of the valve gear in a diesel engine can be caused by __________. prolonged high speed operation spring surge worn valve seats excessively tightened spring retainers Main Engines
D What will cause valve stem blow-by to the valve section shown in the illustration? Illustration MO-0030 A cracked lower spring plate. Worn, broken or stuck compression rings. Damaged rubber rings on the valve seat insert. Defective rubber seal rings in the valve guides. Main Engines
C Worn diesel engine intake valve guides can result in __________. increased engine breathing efficiency excessive valve lash excessive lube oil consumption lower than normal fuel consumption Main Engines
C Worn main bearings will cause the compression ratio of a diesel engine to __________. remain the same increase on compression; decrease on expansion decrease increase Main Engines
B Which of the conditions listed could cause the cylinder relief valves on a large, low-speed, propulsion diesel engine to lift? Plugged injector nozzles Excessive fuel injection Incorrect crankshaft clearances Very late injection timing Main Engines
B The ring lands on a large, low-speed, main propulsion diesel engine piston may crack due to __________. high main lubricating oil system temperature insufficient ring groove clearance insufficient cylinder liner wear contaminated lubricating oil Main Engines
B When inspecting pistons, liners, and rings of a large two-stroke/cycle diesel engine through the cylinder ports, a wet piston crown would indicate a __________. faulty oil ring leaky fuel injector faulty piston lubricator broken compression ring Main Engines
D The most practical way of detecting an overload in one cylinder of an operating large, low-speed, main propulsion diesel engine is to __________. listen for combustion knock in that cylinder isolate each cylinder and inspect the injector check the cylinder exhausts for black smoke check the cylinder exhaust temperature frequently Main Engines
B One method of determining crankshaft misalignment is by __________. laying a straight edge across the crank webs at the crankpin and measuring the distance to the crankpin in two places taking micrometer readings between the crank cheeks opposite the crankpin every 90 of crank angle rotation measuring the crank drop on either side of each crank throw while the crankshaft is slowly rotated through one revolution rotating the crankshaft through one revolution, pausing each 90 of rotation to measure bearing clearances, top and bottom Main Engines
A A main propulsion diesel engine crankshaft bearing lacking sufficient 'crush', will __________. tend to rotate with the journal pound under load have a thicker layer of Babbitt be lubricated more easily than with sufficient crush Main Engines
D Which of the following procedures should be carried out to permit the continued operation of a crosshead engine with a leaky after cooler? Bypass the after cooler to operate at sea speed. Switch to diesel fuel and run at reduced speed. Nothing needs to be done due to the low heating value of heavy fuel. Blank off the cooling water lines and run at reduced speed. Main Engines
A While at sea, the first engineer reports the jacket water expansion tank water has become discolored and has a smell of exhaust on a slow speed two stroke engine. Which would be the most likely cause? A cracked cylinder liner, cylinder head or exhaust valve cage An open turbocharger casing drain valve A leaking exhaust manifold A leaking waste heat boiler tube Main Engines
C A diesel engine emits blue exhaust smoke as a result of __________. a light load excessive compression pressure excessive cylinder lubrication cold intake air Main Engines
b While inspecting diesel engine combustion space components, which components would you consider for particular scrutiny for evidences of high temperature corrosion? Exhaust valves and seats, upper circumference of cylinder liner. Exhaust valves, exhaust valve seats, piston crowns, cylinder heads and upper circumference of cylinder liners. High temperature corrosion does not effect these components. Undersides of cylinder heads, piston crown and exhaust valve. Main Engines
D Before any auxiliary diesel engine hydraulic starting system is opened for servicing or repair, you must __________. place all control levers in the 'HOLD' position ensure that the hydraulic fluid reservoir is full block all hydraulic hoses using high pressure covers bleed off all hydraulic pressure from the system Main Engines
D Starting a large low-speed propulsion diesel engine on diesel fuel during cold weather conditions, will be made easier by __________. increasing the quantity of starting air increasing the lube oil pressure heating the engine fuel supply heating the engine coolant Starting Systems
A Which of the routine maintenance procedures listed is required for starting air receivers? Frequent draining of accumulated moisture. Frequent testing of relief valves. A close watch on temperature to prevent fluctuations in pressure. Frequent cleaning to remove oil and foreign matter. Starting Systems
C When starting a diesel engine at temperatures below 70F, the frictional resistance to turning will be __________. reduced by increasing lube oil pressure controlled by reducing the compression ratio proportional to the lube oil viscosity eliminated by heating the intake air Starting Systems
B Starting air check valves are held firmly on their seats by __________. cam rollers on the camshaft spring force air pressure on top of the valve differential piston air pressure on the bottom of the valve differential piston Starting Systems
C In addition to the main starting air compressor, another air compressor, driven by a separate power source, is installed to __________. provide air for engine scavenging provide air for engine supercharging supply a backup source of starting air supply the independent source of reversing air Starting Systems
B Where is the air charge for an air starting system stored? Air compressor Pressurized tank Distributor assembly Cylinder check valve Starting Systems
D A two-stroke/cycle diesel engine requires less starting air than a four-stroke/cycle diesel engine, of equal displacement, because the two-stroke/cycle diesel engine __________. has little or no internal friction has a lower effective compression ratio operates with scavenge air under a positive pressure operates without energy absorbing intake and exhaust strokes Starting Systems
D An accumulator used in a hydraulic starting system is generally located between the __________. pump and the compressor storage tank and the pump starting motor and the reserve tank pump and the starting motor Starting Systems
C Which of the listed diesel engine starting systems is most susceptible to difficulties in cold weather? Direct cylinder admission air start Hydraulic Electric Air motor starting Starting Systems
C Starting systems for large, direct reversing, main propulsion diesel engines are usually __________. hydraulic starting motor electric starting motor direct air admission vane type air motors Starting Systems
B Which of the following statements is true concerning the air starting valve, labeled "III", as shown in the illustration? Illustration MO-0046 During normal engine running, the air starting valve opens and closes constantly due to cam
action.
The air starting valve is opened by cam action. When starting air is secured, the air starting valve is closed. When starting, the air starting valve is held open by air pressure. Starting Systems
D The pilot valves in an air pilot starting system for a two-stroke/cycle, direct-reversing, main propulsion diesel engine are operated by either a ported distributor disc or a/an __________. regulator valve quick opening main air valve pilot air start check valve individual cam for each pilot valve Starting Systems
A During the starting of a diesel engine, compression gases are prevented from backing into the air starting system, shown in the illustration, by the __________. Illustration MO-0046 cylinder air starting check valves individual distribution valves high pressure in the starting air manifold air starting control valve Starting Systems
A A six-cylinder, four-stroke/cycle diesel engine is fitted with a rotary distributor type air starting system. The speed of the rotating distributor disc is __________. one-half engine speed the same as engine speed twice engine speed four times engine speed Starting Systems
B In a direct cylinder admission air starting system, once the engine begins to fire, the air starting check valve illustrated, is closed by __________. Illustration MO-0107 the starting air pressure the spring force and cylinder pressure a valve actuating cam a pneumatic bellows assembly Starting Systems
C When an air started, four-stroke/cycle diesel engine is being cranked over, the starting air is admitted to each cylinder during the beginning of its __________. intake stroke compression stroke power stroke exhaust stroke Starting Systems
D In a medium-speed marine propulsion engine equipped with direct admission air starting valves, the cylinders without air starting valves fire first because the __________. operation is under higher compression fuel is admitted only to these cylinders during cranking compression is released during starting by opening the exhaust valve cylinders are not chilled by the expansion of the starting air Starting Systems
B Air motors used for starting some auxiliary diesel engines are generally the type known as a/an __________. accumulator motors vane motors gear motors plunger motors Starting Systems
A Which of the following operating characteristics of the Bendix drive friction clutch is associated with a Bendix drive starter? Helps absorb the shock when the pinion engages the flywheel ring gear. Disengages the pinion from the flywheel ring gear. Engages the pinion with the air start distributor. Prevents the pinion starter from overrunning on the starter shaft. Starting Systems
B A Bendix drive starting motor disengages the drive gear from the flywheel by __________. spring force having the flywheel impart a torque to the starter pinion rotating of the starting cam applying accumulator pressure Starting Systems
D The pinion of an auxiliary diesel electric starting motor normally engages the flywheel ring gear by means of a/an __________. automatic follow-up magnetic type coupling muff coupling and release Bendix drive or similar mechanism Starting Systems
B Electric starting motors for diesel engines require high current for operation and __________. require a generator as a source of power will carry a 100% overload for a brief period require a current/voltage regulator for proper operation will overheat if operated continuously over 10 seconds Starting Systems
B Auxiliary diesel engine electric starting motors use __________. 400 cycle per second motor-generator power battery power direct current
low amperage, high voltage AC power
alternating current transformers Starting Systems
C Diesel engine electric starting motors generally require heavier duty motors and operate at higher voltages than comparable starting motors for gasoline engines due to __________. higher speed required lower starting temperatures higher compression pressures
flywheel effect Starting Systems
B Which internal combustion engine starting system uses a vane type fluid motor? Jet flow Compressed air Electric Centrifugal Starting Systems
A The illustration is of a/an __________. Illustration MO-0044 air driven starter motor assembly power take-off driven, vane type, air compressor air driven DC generator battery powered, electric motor driven vane type, hydraulic pump Starting Systems
D Hydraulic starters are installed on many lifeboat diesel engines instead of comparable air start systems, because __________. hydraulic starters are the least expensive of all starting systems the system does not require high pressure piping hydraulic systems turn diesel engines at higher rates of speed than air starters the system can be manually recharged Starting Systems
A Which type of starter motor is normally used in a diesel engine hydraulic starting system? Axial piston Centrifugal Precision gear Turbine drive Starting Systems
B When an engine fitted with a hydraulic starting system starts up, the starter is protected from the higher speed of the engine by __________. the immediate increase in hydraulic pressure the overrunning clutch closing the starting check valves the pivoting of the shaft from being engaged with the flywheel Starting Systems
A The purpose of the engine-driven hydraulic pump in an auxiliary diesel engine hydraulic starting system is to __________. restore hydraulic pressure in the accumulator after starting engage the starter motor with the flywheel fill the sump and prevent low level in the system bypass the hydraulic motor when the engine is running Starting Systems
B In a Bendix starter drive, the pinion engagement with the flywheel ring gear is initiated by __________. Bendix spring pressure starter drive shaft rotation a differential spring solenoid throw out action Starting Systems
A In a diesel engine starting motor equipped with a Bendix drive, the pinion moves and meshes with the flywheel ring gear due to __________. the shaft sleeve spiral helix and relative rotation between pinion and starter shaft shifting levers of solid mechanical linkage centrifugal force developed from rotation electromotive force developed at the flywheel Starting Systems
D An oil-operated, direct-reversing mechanism on a large, low-speed, main propulsion diesel engine, can serve to __________. bring the respective cam under the fuel pump roller rotate or displace the camshaft according to engine design bring the respective cam under the air distributor pilot valves All of the above. Starting Systems
A In order to reverse the rotation of a two-stroke/cycle loop scavenged, direct reversing, propulsion diesel engine, the cam positions must be changed for the __________. starting air and fuel pumps
piston cooling pumps
exhaust valves
All of the above. Starting Systems
D The component labeled "A" on the engine reversing device shown in the illustration, performs its function by transmitting __________. Illustration MO-0125 an electric voltage which energizes solenoids to de-clutch the engine
a fuel oil pressure signal which reverses the engine governor control cylinder
a hydraulic pressure which shifts an alternate set of camshaft followers to ride on the engine camshaft a pneumatic signal which activates a hydraulic control cylinder allowing the camshaft to shift axially Starting Systems
D The cylinders labeled "B" and "C" in the illustration are used to __________. Illustration MO-0125 provide oil to lubricate component "F"
 o
supply a specific volume of oil to the engine governor provide the required quantity of grease at specified maintenance intervals supply the force required to shift the engine camshafts axially to reverse engine rotation Starting Systems
B Intercoolers installed on starting air compressors, reduce the possibility of __________. dust entering the first stage lube oil carbonization discharge pulsations interstage vapor lock Starting Systems
D Which of the following statements is true concerning the air starting valve, labeled "III", as shown in the illustration? Illustration MO-0046 When starting, the air starting valve is held open by air pressure. When starting air is secured, the air starting valve is closed. During normal engine running, the air starting valve opens and closes constantly due to cam

 action.
The air starting valve is opened by cam action. Starting Systems
A During the starting of a diesel engine, compression gases are prevented from backing into the air starting system, shown in the illustration, by the __________. Illustration MO-0046 cylinder air starting check valves air starting control valve individual distribution valves high pressure in the starting air manifold Starting Systems
D In a direct cylinder admission air starting system, once the engine begins to fire, the air starting check valve illustrated, is closed by __________. Illustration MO-0107 a pneumatic bellows assembly the starting air pressure a valve actuating cam the spring force and cylinder pressure Starting Systems
C In a medium-speed marine propulsion engine equipped with direct admission air starting valves, the cylinders without air starting valves fire first because the __________. fuel is admitted only to these cylinders during cranking operation is under higher compression cylinders are not chilled by the expansion of the starting air compression is released during starting by opening the exhaust valve Starting Systems
D Which internal combustion engine starting system uses a vane type fluid motor? Jet flow Centrifugal Electric Compressed air Starting Systems
D Hydraulic starters are installed on many lifeboat diesel engines instead of comparable air start systems, because __________. hydraulic starters are the least expensive of all starting systems the system does not require high pressure piping hydraulic systems turn diesel engines at higher rates of speed than air starters the system can be manually recharged Starting Systems
B When an engine fitted with a hydraulic starting system starts up, the starter is protected from the higher speed of the engine by __________. the immediate increase in hydraulic pressure the overrunning clutch closing the starting check valves the pivoting of the shaft from being engaged with the flywheel Starting Systems
B In a Bendix starter drive, the pinion engagement with the flywheel ring gear is initiated by __________. Bendix spring pressure starter drive shaft rotation a differential spring solenoid throw out action Starting Systems
B Which of the following operating characteristics of the Bendix drive friction clutch is associated with a Bendix drive starter? Engages the pinion with the air start distributor. Helps absorb the shock when the pinion engages the flywheel ring gear. Disengages the pinion from the flywheel ring gear. Prevents the pinion starter from overrunning on the starter shaft. Starting Systems
D The pinion of an auxiliary diesel electric starting motor normally engages the flywheel ring gear by means of a/an __________. automatic follow-up muff coupling and release magnetic type coupling Bendix drive or similar mechanism Starting Systems
D Auxiliary diesel engine electric starting motors use __________. low amperage, high voltage AC power alternating current transformers 400 cycle per second motor-generator power battery power direct current Starting Systems
D An oil-operated, direct-reversing mechanism on a large, low-speed, main propulsion diesel engine, can serve to __________. bring the respective cam under the fuel pump roller rotate or displace the camshaft according to engine design bring the respective cam under the air distributor pilot valves All of the above. Starting Systems
B In order to reverse the rotation of a two-stroke/cycle loop scavenged, direct reversing, propulsion diesel engine, the cam positions must be changed for the __________. piston cooling pumps starting air and fuel pumps exhaust valves All of the above. Starting Systems
D The component labeled "A" on the engine reversing device shown in the illustration, performs its function by transmitting __________. Illustration MO-0125 a hydraulic pressure which shifts an alternate set of camshaft followers to ride on the engine camshaft an electric voltage which energizes solenoids to de-clutch the engine a fuel oil pressure signal which reverses the engine governor control cylinder a pneumatic signal which activates a hydraulic control cylinder allowing the camshaft to shift axially Starting Systems
D The cylinders labeled "B" and "C" in the illustration are used to __________. Illustration MO-0125 supply a specific volume of oil to the engine governor provide oil to lubricate component "F" provide the required quantity of grease at specified maintenance intervals supply the force required to shift the engine camshafts axially to reverse engine rotation Starting Systems
D Intercoolers installed on starting air compressors, reduce the possibility of __________. interstage vapor lock discharge pulsations dust entering the first stage lube oil carbonization Starting Systems
C You are the Chief Engineer on a Ro/Ro vessel powered by a MAN two stroke, direct reversing, slow speed diesel engine. While maneuvering into New York with the main engine in Bridge control status you receive low pressure alarms on both main air receivers. Both ship's main air compressors are operational and running at the time of the alarms. What should you do? Check the air compressors to be sure they are operating correctly. Take control of the main engine in the engine control room. Check the air compressors to be sure they are operating correctly. Then inform the Captain on the Bridge that the starting air supply is not keeping up with demand and start air pressure should be monitored closely during the reminder of the maneuver. Take control of the main engine and operate the main engine from the engine side in emergency mode. Starting Systems
c A pre-arrival test is being performed with the engine on bridge control. The vessel has a slow speed engine with mechanical starting air system (not electronic). After a stop order, the engine fails to restart in the next ahead direction order. What would be your immediate actions to restart the engine, if the order was still ahead? Inform the bridge that all are working on the problem and they may have to consider anchoring until the problem is resolved. Call the bridge and inform them of the problem. Ascertain that the main starting valve is open and functioning properly and start trouble shooting. Inform the bridge. Take engine room control of the engine, change the engine's direction to astern position and try to restart in that position. When the engine tries to restart, switch back to
ahead and restart.
Call the bridge and inform them of the problem. Ascertain that starting air tanks are up to pressure and are lined up and start trouble shooting. Starting Systems
D During maneuvering on a slow speed diesel engine vessel, a low starting air system pressure alarm is activated. Local starting air receivers' pressure gauges indicate proper pressures, and compressors are running and are 'loaded' up. What could cause the alarm? Malfunctioning starting air cylinder distributor valves. A stuck open air starting valve on one of the engine cylinders. Malfunctioning, stuck open, main engine air starting valve. Faulty system alarm pressure switch and/or a fault in the alarm circuit. Starting Systems
C The starter control valve in the hydraulic system shown in the illustration is malfunctioning. Before removing the valve, you must first __________. Illustration MO-0049 drain the reservoir remove all plugs from the system bleed off all accumulator pressure in "E" ensure that the accumulator piston is in the charged position Starting Systems
A Which of the listed items should be secured before performing any maintenance on a solenoid operated air start valve? Electric power and starting air Lube oil standby pump and control air Hydraulic switch and engage jacking gear Motor drain and pneumatic control system power Starting Systems